Facebook?

So, I've never had a...what do you even call them--a profile(?) on a networking site such as myspace of Facebook. I've just blogged and that's been plenty fine and good for me. My cousin has a facebook account and one time she showed me about a million people that I went to high school with and I did think that was pretty intriguing, but I never did take the plunge.
However, I'm thinking more and more about doing it. I think it would be fun to find out where people ended up and what they are doing. I'm always fascinated by people--isn't that one part of the draw to blogging?
So, what do you think? Do you have a Facebook account? If not, why? Do you like it more than blogging? What do you post on your Facebook account that you don't post on your blog? Lots and lots of questions...