Agree completely. Regardless of whether or not android users would miss their widgets, a big problem is that, just judging from a small local sample of friends and coworkers, no one has any idea just what the point of the app is. Facebook's marketing campaign around this thing is absolutely terrible. From their constant advertising, I've surmised that it's, I don't know, some kind of live updating slideshow of friend's photos? My curiosity is not piqued enough to even bother an install.
The marketing of it is really just terrible, which really puts me off. The strategy of "be even more of a non-current-situation-engaging dickhead in social situations with our app!" I don't see a commercial of someone in an art gallery, ignoring the paintings, ignoring the person their with, and generally just being insufferably over connected and think "y'know, I should get that app."
May just be getting old though..