Twitterfall is an Excellent Keyword-Based Tweet Tracker
Twitterfall is quite possibly the best Twitter keyword tracking tool I’ve seen so far. It’s got a simple interface but packs a lot of features. You can change the speed of the tweet stream from 0.5 tweets per second to a dizzy 10 tweets per second. In terms of tracking you can choose the specific location of the tweets and include as many custom keywords as you want, all of them will appear in the same stream.
If you log in to Twitterfall you can also reply or retweet the tweets you see without opening a new window or tab. Very useful if you want more feedback from the specific Twitter user. I can imagine how useful Twitterfall would be for journalists, business reps, news junkies, bloggers and other Twitter enthusiasts.
Another advantage is that you can see your normal timeline as you would normally see it in Twitter if you log into their service, which means you can use Twitterfall in place of the web interface. The only downside is that Twitterfall feels a little unresponsive at times, especially when I change or add custom keywords for tracking. There always seems to be a slight lag, but its nothing worrying.