ChatGraph - Realtimeish twitter topic monitor

I often use Twitter search to see what people are saying about various subjects, but got annoyed at having to hit refresh all the time to see newly updated tweets. I also wanted to display the messages using a time graph, as I had in my referrer logs. So after a few fun hours of JavaScript and a few interesting minutes of Google App Engine, I am happy to release ChatGraph; it allows you to monitor what people are saying about something, and get a quick overview of how frequently they're talking about it.