I had a ton of respect for this kid leading up to this fight, but his behavior has seemed very odd in recent months. At the very least he's unfocused; at worst, he's starting to believe his own press clippings or web printouts.
I don't think a one dimensional Quinton is enough to take the belt, but perhaps a crafty Machida, or a game savvy Rashad. Dan Henderson, Thiago Silva and then of course Anderson Silva, all have the potential to give him a great fight.
If anything will be his undoing, it will be his hunger and focus, not his physical talent, which is top 5 in the MMA game for sure.