Hi, I feel a little bad that I always use twitter-dev to whine about bugs in the search API. But it's really great and you can build interesting things on top of it! We just put up an experimental search/text analytics app that clusters tweets based on key phrases and terms relative to a specific search query. It can sometimes be helpful for knowing *why* a term is trending, or for finding different types of sentiments people have toward something. There's also a more research-y direction for discovering related concepts for a query.
The first draft, experimental version is up; please play around with it if you're in to this sort of thing. http://tweetmotif.com http://anyall.org/blog/2009/05/announcing-tweetmotif-for-summarizing-twitter-topics-with-a-dash-of-nlp/ -Brendan
