Yeh, that'd be possibly if he didn't have a great season the season before that. He's had 2 brilliant seasons, he's the best player in the world, and I'd say the only player in the world that could possibly replace him would be Lionel Messi, but he's not leaving Barca any time soon. He may be abit of a twat, but I'd still want him at my football club. If I was a United fan I wouldn't want him leaving.
If he'd done something similar to what Robinho did, a press conference telling everyone he's off to Madrid then fair enough let him go, but he said nothing throughout the summer, he said Real are the team he dreams of playing for 1 day, but he didn't say "I'm off, cya". I wouldn't let Ronaldo leave, and you know if Sir Alex hasn't let him go he must want to stay, he's not shy in letting players go if they want to leave, look at Ruud and Beckham for example. The fact is, if Ronaldo had told Sir Alex that he wanted to leave, he'd have shipped him out, he doesn't like having players at his club that don't want to be there, no matter who they are. He's going to stay at United, and I hope he does, I love watching the bloke play, he's brilliant.