I have a Facebook account but I'm pretty careful how I set it up. People who are not my friends can see very little about me, and I am mindful of what I post. I do enjoy the possibility it affords to keep in touch with long-distance friends, even if of course it's limited in many ways...

I also have a Twitter account. I use it mostly to receive and relay news that is not personal. On my "follow" list I have a bunch of journalists, and that's how they use it. I have "unfollowed" people who were chatty about their personal lives on Twitter.

And, by the way, Lance Armstrong is on Twitter. I find some of his tweets interesting but it annoys me when he says he's "driving the kids to school" (why doesn't he get a tandem with a trail-a-bike?) and other stuff of his daily life like that. To me the point of Twitter is not to know the flavour of people's toothpaste, but I realize I'm part of the minority.