I have a friend who posts a new picture of himself, on Facebook, at least twice a week. In addition his posts are always about him. He's the worst offender but I've noticed lot's of others how have fallen into the self obsession habit. I found an article that sums up my feelings pretty well. http://meteuphoric.wordpress.com/2010/02/04/how-does-facebook-make-overt-self-obsession-ok/
BTW, I'm not thinking of anyone reading this so don't get defensive and think..he's talking about me.