Are you just saying that because he got his teeth fixed? :P
Yeah, Rooney's never really been bad for United. And in 2011/12 he scored 34 goals for us, just his output dips when a main man takes the weight of his shoulders (Shocker) such as Ronaldo or Van Persie. But if he genuinely does want to go just because Van Persie's too much competition for him, then he needs to grow a pair - in 2010 he complained "we aren't signing world class players, I'm leaving" (to be fair, other than Cantona and Van Persie, we've never really signed players who're already world class). Now it seems like he's been disappointed because we've bought another world class player and he's not the undisputed No.1. Secretly I think he was celebrating when we sold Ronaldo.
Whatever the truth is though, I really wish he'd actually speak out in person. The most annoying thing about the Rooney / Suarez / Bale sagas is that the main men involved aren't speaking out, we're left hanging on the every word of "close sources" - in other words, someone at the Daily Sport made it up and circulated it to other journalists :P