Do you Tweet?

I've never been one who has to be the first to try all the new tech stuff. That's why this fairly new social networking site -- Twitter -- is still foreign to me. I've been hearing a lot about it lately. It seems like the information and the name dropping has been coming from everywhere. I did a Google search and read the Wikipedia page on the subject, but I'm still a little lost in some of the details.

Do any of you use Twitter yourselves? What do you like or not like about it? Why did you join, or not join if you're resisting the movement? I'm curious to know your reasons...