Would be a great back-and-forth battle, but I see Nick coming out with the victory.
I think Bisping would be forced to trade with Nick and Nick will win the exchanges and Bisping will start to slow down from the punishment.
Bisping has some good cardio, I know, but taking that kind of punishment will slow you down, especially when your opponent is constantly looking to drill you with shots to the midsection. Bisping has good cardio, but Nick's is definitely better and usually fights at a higher pace than Bisping does. Bisping has had some fights where he's used tons and tons of volume, but pretty much Nick's entire career has been like that. Nick can take the punishment and dish it back out, I'm not sure if Bisping will be able to do that. It's going to be a back-and-forth war until somebody falls, and I believe Bisping will be the one that falls. You are not going to out-cardio or out-brawl Nick Diaz. You just aren't. He's going to win that every single time and I think Nick gets into his head and Bisping will be forced to exchange with him and Nick will eventually just start smacking him around.
Bisping can fight a high pace, but I'm not sure if he'd be able to fight and be successful at Nick's pace.
If Nick sees you're slowing down, he will pour it on and odds are you're going to either get beaten down the whole time, or you're going to crack and not be able to take the punishment.
I think Nick forces a brawl and Bisping slowly but surely starts to wilt. I don't see Bisping being able to stay off the fence for the entire fight and I think Nick would get into his head and make him emotional, and it will only make things worse for Bisping because he will get sucked into Nick's kind of fight and you are not going to beat Nick that way.
Bisping can still pull it off though. It depends on how he shows up. If he tries to go at a very high pace and trade with Nick, he's going to get smacked up. If he uses that footwork and cuts the angles, stays at range and keeps Nick at bay with kicks (leg kicks, front kicks to the head and body) and straight punches, he could take it. He will really have to mix it up to keep Nick off of him. If Nick can successfully close the distance, it's going to be a bad night for The Count.
So, I take Nick either KO/TKO late in the fight, or it will go to decision and Nick will take the UD. I don't see Bisping being able to keep Nick off of him and I think he'll slowly get sucked into a brawl and Nick will light him up.