I set up a Twitter account this weekend and love it. Twitter is almost exactly what I want in a tool for micro-blogging.
And even better, Twitter is very API-friendly, so it will be easy to integrate the comment stream with this site or any number of other applications or devices. For example, Niall points to the pretty OSX application, Twitterrific:
I swear, if I didn't love my job, I'd go ask Ev for one.
Add me to your friends list.