"Daddy, where were you when privacy died?" "I was on hacker news commenting through facebook connect."
On the one hand, I don't have to use facebook. On the other hand, I worry about the immense asymmetry of information that facebook has about me even if I don't join. If I'm a hole in the social graph (because all my friends use it regularly to post pictures, etc. of me), it doesn't take much effort for them to fill in the data on me.
It would take a hell of a heuristic for facebook to fill in holes in the social graph. Without some very intelligent fuzzy name matching, facial recognition, and textual analysis of your friend's profiles and walls (if you ever are mentioned), not having a profile ID basically means they have nothing on you that can be extracted in an automated fashion.
A human investigator, however, would be intelligent enough to build a profile on you from your friends' submitted information, so there still is some cause for concern. But at least you are safe from datamining.
On the one hand, I don't have to use facebook. On the other hand, I worry about the immense asymmetry of information that facebook has about me even if I don't join. If I'm a hole in the social graph (because all my friends use it regularly to post pictures, etc. of me), it doesn't take much effort for them to fill in the data on me.