I guess I use it differently, because for my uses, Facebook and Twitter are almost equal contenders currently. Nobody in my social group ever uses Facebook invites, so the main thing is the status updates and replies. Facebook has somewhat of an advantage over Twitter on that still due to: 1. more generous length limits; and 2. a series of replies to a status going into a thread instead of the main flat status-update namespace; and 3. "likes" are a useful way of acknowledging a status without actually replying. Twitter's main advantage is that it feels less spammy and has nice 3rd-party clients; I'm always playing whack-a-mole with hiding Zynga games and Quizzes from my FB feed.