I've been using it for a little bit now, and while I don't want to give my review away completely, I would definitely suggest hitting up your local Sprint store to see how much you like it. It's worth the trip. . . trust me.
Anyway, if you aren't on Sprint, don't want to be on Sprint, or would like your Galaxy S II to have a shorter name, you'll have to wait. Both AT&T and T-Mobile models haven't been released yet, and it might be a little while until they are.[Engadget]