So, you’re a baseball fan? Us too! In fact, there are tons of fans, teams, players and news sources sharing loads of useful baseball information right now as playoff fever spreads. And, spreading it is. From Roy Halladay’s no-hitter to Tim Lincecum’s 14-strike-out game last night, baseball related terms have been leading Twitter’s trending topic’s this week.

Here are some tips to help you find the best baseball sources on Twitter so you, too, can share in the experience.

By all accounts Twitter is on a roll. We've redesigned our web site to great user feedback. Our user and usage numbers are growing at a rapid clip all around the world. We’ve launched an early, but successful, monetization effort. And, many top engineers, product designers, sales people and other key folks have joined our quickly growing team.

In fact, there are 300 people working at Twitter today—compared to about 20 when I took the CEO job two years ago. Back then, people were creating about 1.25 million tweets a day—compared to 90 million today. In those same two years, we grew from 3 million registered users to more than 165 million today.

The challenges of growing an organization so quickly are numerous. Growing big is not success, in itself. Success to us means meeting our potential as a profitable company that can retain its culture and user focus while having a positive impact on the world. This is no small task. I frequently reflect on the type of focus that is required from everyone at Twitter to get us there.

This led to a realization as we launched the new Twitter. I am most satisfied while pushing product direction. Building things is my passion, and I’ve never been more excited or optimistic about what we have to build.

This is why I have decided to ask our COO, Dick Costolo, to become Twitter’s CEO. Starting today, I’ll be completely focused on product strategy.

When I insisted on bringing Dick into the COO role a year ago, I got a lot of questions from my board. But I knew Dick would be a strong complement to me, and this has proven to be the case. During his year at Twitter, he has been a critical leader in devising and executing our revenue efforts, while simultaneously and effectively making the trains run on time in the office. Dick can be even more effective at this now because Ali Rowghani, Adam Bain, Mike Abbott, Katie Stanton and Kevin Thau joined our leadership team this year and are having a big impact. Given Dick’s track record as a three-time successful CEO, I’m confident we can make this a smooth transition.

I’m extremely proud of how far Twitter has come in the last two years. And, I couldn’t be more excited about where our amazing team will take it next.

When we launched Promoted Tweets back in April, we said that we would be doing lots of experimenting and iterating, as is typical with everything else at Twitter. Since then, we’ve done and learned a lot – such as adding Promoted Trends to our suite of Promoted Products and making those products available to an ever-widening audience of users and advertisers.

Today, we’re entering a new phase in our efforts. We are launching Promoted Accounts, a new ad product that gives added value to Twitter users. We will also make our Promoted Products available through our partners for the first time.

Promoted Accounts
We’re launching Promoted Accounts as part of “Suggestions for You”, which suggests accounts that people don’t currently follow and may find interesting. Promoted Accounts helps introduce an even wider variety of accounts people may enjoy.

Promoted Accounts are suggested based on a user’s public list of whom they follow. When an advertiser promotes an account, Twitter’s algorithm looks at that account’s followers and determines other accounts that those users tend to follow. If a user follows some of those accounts, but not the advertiser’s account, then Twitter may recommend the advertiser’s Promoted Account to that user. For example, a lot of people who follow several gaming-related accounts also follow @xbox. If someone follows gaming-related accounts, but not @xbox, Twitter may recommend @xbox to that person.

We currently display “Suggestions for You” in the side panel on the right side of your logged-in Twitter.com homepage. Starting this week, you may see a Promoted Account as one of these suggestions. When there's no relevant recommendation, no Promoted Account will show.

Since we will only be testing Promoted Accounts with a handful of companies initially, there’s a chance that you might not see one at first. We look forward to getting interesting Promoted recommendations to you soon.

Promoted Products for Partners
We are also beginning to make Promoted Tweets and Promoted Trends available beyond Twitter.com – something we have discussed doing since launching Promoted Tweets in April.

We are testing syndication of Promoted Products with a select number of partners – HootSuite is launching today, and others are on the way. These partners will run Promoted Tweets in search and highlight Promoted Trends, sharing in Twitter’s revenue for these products.

This is an important step for these partners and for the many highly active Twitter users who spend considerable time on third-party applications. As with all Twitter launches, we’ll review the initial feedback and determine where we take it from here.

And more
Along with these more noticeable changes, we made additional tweaks to our Promoted Products suite last Friday. We bumped up the Promoted Trend to the top of the trending topics list because we’ve been pleased with the quality of Promoted Trends and people are finding them useful. And you may have noticed that if you click on a Tweet with a hashtag that a brand is promoting, you will see a Promoted Tweet among the related Tweets in the details pane.

It’s been a busy but exciting few months for Twitter’s advertising team. We’ve launched 3 major products in the past 6 months. We’re working with over 40 advertisers – nearly 80% of whom have already become repeat buyers in this short period of time – and we have an exciting roadmap to expand to more advertisers. Plus, the new Twitter creates exciting opportunities to be creative with Promoted Tweets by combining text with pictures and video.

Thanks to our growing engineering and sales teams, you can look forward to more innovative ways to connect people with their favorite brands and interests.

People often tweet about TV shows as they’re watching them. Additionally, media companies are increasingly finding new ways to incorporate Tweets into their programs. Take, for example, Jimmy Fallon or the Video Music Awards in September. Tweets aren’t just about TV shows; they are part of them.

We’ve long discussed what the interplay between Twitter and television would look like. As a first step, today we’re announcing Twitter for Google TV. It brings Twitter to a platform that merges the Internet and TV into one experience.

The application has most of the features and functionality that you’d expect from Twitter. It makes it easy to look through Tweets, @mentions, and favorites. When you click on a Tweet, you can reply, retweet, favorite, or share it. You will also see additional options depending on the content of the Tweet. For example, you can visit a URL or click a hashtag to search for it on Twitter. If a user is mentioned, you can visit that user’s profile to see their Tweets or follow them. And if there is a link to a photo or video, you can see a thumbnail version. Clicking the link will take you to the site so you can see a larger version of the photo or watch the video.

Additionally, the search box provides access to trending topics and recent searches, so you can quickly check out popular topics and revisit past searches. Twitter for Google TV, which is preinstalled, also lets you share videos, web pages, pictures, and other content on Twitter – just look for the “Share” option and select Twitter.

This is just the beginning of what could be possible at the intersection of Twitter and television. We’re excited to see what’s next.

On a sunny September Sunday inside a non-descript trailer in downtown Los Angeles, media evolved.

There—in the shadow of the 2010 MTV Video Music Awards, next to an outdoor stage where Justin Bieber would soon perform—web developers and TV producers were working together, leaning into laptop screens and NTSC monitors, bringing the real-time conversation around the VMAs to life on live television for 11.4 million viewers.

While Twitter is about all types of information, the ways that the service fits into media have long been important to us, and increasingly, media makers are weaving Tweets into the very fabric of their content. Look at segments like Jimmy Fallon's Late Night Hashtags, where Tweets from viewers aren't a gimmick; they're great content. Look at sites like the Huffington Post, where Tweets underscore and amplify the headlines whenever there's a big story brewing. Look at live shows like the VMAs, where Twitter came alive on a 95-foot-wide screen.

Now, with the launch of the new Twitter, the ways that media fits into Twitter.com are just as important. Whenever there's a new movie release, a TV show premiere, a big football game, or a breaking news story, people are talking about it on Twitter. With the new Twitter, they're seeing glimpses of it, too, because photos and videos are now presented as part of the core Twitter experience.

We’re working hard to display photos and video from more sources in the details pane. We also look forward to future brainstorms both inside and outside of Twitter about what will be possible. Imagine a Tweet about a breaking news story that pulls a live video stream and eye-witness photos from the scene into the details pane. Imagine a Tweet from a football game that includes a highlight clip, edited down and posted in near real-time. Imagine Tweets from a music festival curated to present the best images—from the crowd, from behind the scenes, and from up on stage.

In that trailer out behind the VMAs, it was web developers and TV producers working together to find the best Tweets and tell a story across platforms. It was code working with content, and that’s going to be a crucial combination in the months and years ahead. In the next evolution, you’ll see Tweets enrich and enliven great content—and you’ll see that content spread out and make the new Twitter better for everyone.

The trailer is optional.

There can be a new definition of success for startups of all shapes and sizes. Ev and I spend an hour with every new Twitter employee as part of the orientation process and during this hour we cover quite a bit of material—including our mistakes and our aspirations. New team members learn that with their help we will make a positive global impact, we will build a successful business, and we will have fun along the way. Ev often punctuates this point emphatically stating that success is only defined by all three of these goals.

Young companies like ours are particularly well positioned to build altruism into the corporate culture from an early stage and that is something we have made central to our work at Twitter. Our Hope 140 site highlights some of the work we have done in this area but I'd like to call attention to a specific project that has been maturing for about a year. A world in which all children can pursue a quality education is something worth celebrating. This weekend, our Fledgling Initiative has finally ripened and we want you to join the cause.

The Fledgling Initiative was hatched to craft awesome wine for the benefit of Room to Read, a non-profit organization extending literacy and educational opportunities to children worldwide. Every bottle and every case of Fledgling wine sold will help promote literacy in Uttarakhand, India. These wines are being made using some of the best vineyards in California by the acclaimed winemaking team at Crushpad. Incidentally, 2009 appears to be an excellent vintage in California, potentially one of the best of the decade.

Twitter employees have been involved in every aspect of the wine making process from harvesting to crushing to bottling. We put effort into this because we believe in the cause and because it has been a fun and rewarding experience. We hope you will order and enjoy some our Fledgling wine. Twitter and Room to Read believe that all children, regardless of gender or background, have a right to education. By empowering children through this lifelong gift, we envision a world in which people are able to realize their full potential.

The short story: This morning at 2:54 am PDT Twitter was notified of a security exploit that surfaced about a half hour before that, and we immediately went to work on fixing it. By 7:00 am PDT, the primary issue was solved. And, by 9:15 am PDT, a more minor but related issue tied to hovercards was also fixed.

The longer story: The security exploit that caused problems this morning Pacific time was caused by cross-site scripting (XSS). Cross-site scripting is the practice of placing code from an untrusted website into another one. In this case, users submitted javascript code as plain text into a Tweet that could be executed in the browser of another user.

We discovered and patched this issue last month. However, a recent site update (unrelated to new Twitter) unknowingly resurfaced it.

Early this morning, a user noticed the security hole and took advantage of it on Twitter.com. First, someone created an account that exploited the issue by turning tweets different colors and causing a pop-up box with text to appear when someone hovered over the link in the Tweet. This is why folks are referring to this an “onMouseOver” flaw -- the exploit occurred when someone moused over a link.

Other users took this one step further and added code that caused people to retweet the original Tweet without their knowledge.

This exploit affected Twitter.com and did not impact our mobile web site or our mobile applications. The vast majority of exploits related to this incident fell under the prank or promotional categories. Users may still see strange retweets in their timelines caused by the exploit. However, we are not aware of any issues related to it that would cause harm to computers or their accounts. And, there is no need to change passwords because user account information was not compromised through this exploit.

We’re not only focused on quickly resolving exploits when they surface but also on identifying possible vulnerabilities beforehand. This issue is now resolved. We apologize to those who may have encountered it.

Twitter has always been about getting a lot in a little. The constraint of 140 characters drives conciseness and lets you quickly discover and share what's happening. Yet, we've learned something since starting Twitter—life doesn't always fit into 140 characters or less.

Today, we’re introducing a new, re-engineered Twitter.com that provides an easier, faster, and richer experience.

On the site, you’ll see the familiar timeline, yet underneath each Tweet is a handful of information, deeper context and even embedded media. Simply click on an individual Tweet and a details pane slides out on the right and reveals this content.

You can find out more about the enhancements on this information page. Here are some highlights:

• New design. The site has a cleaner timeline and a rich details pane that instantly adds more impact to individual Tweets while still maintaining the simplicity of the timeline. And, experience infinite scroll -- you no longer have to click “more” to view additional Tweets.
• Media. Now, it’s easy to see embedded photos and videos directly on Twitter, thanks to partnerships with DailyBooth, deviantART, Etsy, Flickr, Justin.TV, Kickstarter, Kiva, Photozou, Plixi, Twitgoo, TwitPic, TwitVid, USTREAM, Vimeo, yfrog, and YouTube.
• Related content. When you click a Tweet, the details pane shows additional information related to the author or subject. Depending on the Tweet’s content, you may see: replies, other Tweets by that user, a map of where a geotagged Tweet was sent from, and more.
• Mini profiles. Click a username to see a mini profile without navigating from the page, which provides quick access to account information, including bio and recent Tweets.

These changes will roll out as a preview over the next several weeks starting with a very small percentage of registered accounts tonight. During the preview, you'll be able to switch back and forth so you have time to grow accustomed to the way things work. Eventually, everyone will have the updated version of Twitter.com. We are incredibly proud of the work the Twitter web team has accomplished. We hope you are too!

It’s New York’s biggest week in fashion, and Twitter is bringing you a front row seat.

Starting today, Twitter and American Express will provide real-time access to Fashion Week featuring exclusive photos, commentary, and first looks at the top names in fashion.

Go to twitter.com/fashionweek to join the conversation and get insider access to the best Fashion Week has to offer.

• Runway Shows: see the hottest looks straight from the runway, courtesy of @WomensWearDaily
• Designers & Fashion Insiders: get up close and personal with interviews from top designers and fashion insiders courtesy of @AmericanExpress
• The Scene: check out the backstage drama, including candid shots of models, designers and celebs, courtesy of @Modelinia
• Beauty: learn the newest beauty, make-up, and hair techniques, courtesy of @AskBobbiBrown, @Aveda, @BumbleandBumble, @Smashboxartists, and more
• Daily Recap: look through the best of each day after the shows, curated for top trends, emerging themes, and unexpected surprises, courtesy of @Bergdorfs

Follow @nyfw to get the latest Fashion Week information, including a “Little Black Book of Hashtags” and details on your favorite designers’ shows.

Just over four months ago, at Chirp, our Twitter developer conference, I talked about how "Twitter is too hard" and what we're doing to address that.

One major area of difficulty I highlighted was getting Twitter on your phone. We did iPhone user tests and confirmed that even though there was a plethora of third-party Twitter apps, people were having trouble finding and selecting one because none were called “Twitter.” This kept them from using Twitter at all. For this reason, we acquired Tweetie and turned it into Twitter for iPhone, complete with a new user sign-up experience.

Mobile apps – Everywhere
We quickly understood that we were doing users a disservice by not having a great client on each of the major mobile platforms. So, we took a similar approach with Twitter for BlackBerry (developed by RIM) and Twitter for Android, which launched a new version this week.

This strategy has been quite successful. Total mobile users has jumped 62 percent since mid-April, and, remarkably, 16 percent of all new users to Twitter start on mobile now, as opposed to the five percent before we launched our first Twitter-branded mobile client. As we had hoped in April, these clients are bringing more people into Twitter, and, even better, they are attracting and retaining active users. Indeed, 46 percent of active users make mobile a regular part of their Twitter experience.

How people are using Twitter
Our Twitter for iPhone and Twitter for BlackBerry clients are now two of the most popular ways to use Twitter. This may not be surprising. What may be more surprising are the other top ways people use the service. The following chart shows the top ten applications people have used to access Twitter in the last 30 days. This is based on number of unique users. That is, out of all the people who logged into their Twitter account during the month, what percentage did so via each service. (The total is more than 100% because people often use more than one app.)