Here's IMHO on Twitter.  First of all, you need to make sure you're following people who are interesting, or else you'll just get annoyed.  Some people tweet about their lunch or what they did at work, or what their kid shit out this morning.  I can only assume they don't know how to use instant messaging to tell their buddy's inane crap. 

 In order for you to really get the power of twitter, you have to use the search function and figure out how to use #hashtags and go to trending trackers like twopular.com.  Plus if you use the igoogle stuff you can put a twitter widget in there and see the latest tweets.  I like it mainly for laughs and to see what's going on.