Twitterholic: Who are these people?

Twitter is a social networking tool that lets tell your friends what you’re doing throughout the day. Kinda like a blog where all the posts are 140 characters or less and you make dozens (or more) posts per day. Why would you want to do this? I’m still trying to figure that out but apparently it’s becoming popular. Twitterholic scans the twitter timeline to track popular and prolific twits, er twitter-ers.