I don't poke, tweet, or anything of that kind. I needed a Facebook account to be the admin of my companies Facebook page, I kept it at 0 friends and after months of family and friends trying to add me, thinking I just don't want to add them, etc I invited a few to show them there is nothing to see, then removed them.
Facebook is just a lot of drama, I can see the usefulness of sharing pictures of kids and such with family but it seems the last several years almost every family argument has involved, "Well he/she said on Facebook...".
To me, Facebook just screams "look at me, look at me" - when that's usually the last thing I want to do.