What the Trend
http://whatthetrend.com/

What the Trend helps you find out what’s trending on Twitter and why. They are “The front page of the real-time web™.” When a new topic becomes popular on Twitter, it’s listed as a “trending topic.” These topics may take the form of short phrases (i.e. Michael Jackson) or hashtags (i.e. #iranelection). What the Trend provides a constantly updated list of trending topics from Twitter and allows you and thousands of other people across the world to explain, in a few short sentences, why this item is interesting or important to people right now. Sometimes, it may be a breaking news story. Sometimes it’s just for fun. Either way, their users do a great job of coming up with short, accurate descriptions of why that item is popular. Their vetted descriptions are syndicated to a broad range of websites and applications. You can see WTT definitions on Twitter.com, in Tweetie or Twittelator for the iPhone, on Trendsmap on the web, or in many other places. This has been added to the tools section of Research Resources Subject Tracer™ Information Blog.