Honestly when these fights get made, the 'if it goes out of the first round X fighter wins' type fights, how often does the guy who absolutely needs to win it in the first round actually win?
Vitor can win. It's just so unlikely. And with Bisping being an underdog, you'd be crazy to bet on Vitor.
Vitor's biggest accomplishment is that he's a '2 time' UFC champion. He won the UFC 12 tournament by beating Tra Telligman and Scott Ferrozo and he went 1-2 with Couture in their series with his only win being a freak accident where his glove got caught in Couture's eyelid. He got absolutely trashed by Couture the other two fights.
The guy really has never done anything that spectacular, and the fact people consider him KOing Tank Abbot to be impressive really just says it all.
Bisping is a douche, but he comes to fights with smart game plans and is perfectly happy to grind out decisions when necessary. And that to the fact that Vitor will be a punching bag by round 2, and this is going to be very messy.
How is it unlikely?
Bisping gets clipped every time he fights someone who has power behind their punches, Vitor has that, plus speed and very good follow up ability. I expect this a lot to look like the Rich Franklin fight.