The Arlovski fight coming up has got me thinking. I don't think Arlovski has what it takes to win, and personally think it's a terrible stylistic match up for him. But Fedor has got to lose eventually (anyone that counts that first 'loss' is an idiot), who do you think is going to be the one to beat him?
I personally think Barnett has all the tools to beat him. If he can mentally pull himself together(he already ducked Fedor once), he could definitely put up an extremely competitive fight and come out with a win. Physically, the guy is a monster. One of the few that Fedor would not be able to muscle around, and he's not exactly slow, I don't see Fedor having much of a speed advantage here. While his striking does have a lot of holes in it, he has knockout power and I don't think would be absolutely dominated by Fedor standing. If he tried to keep the fight standing for some reason, Fedor would undoubtedly knock him out. Barnett would be able to get the fight to the mat with superior wrestling, and Fedor isn't exactly known for great take down defense. On the ground I really think Barnett could sub Fedor. He has good enough ground control to stay on top and drop a couple bombs to soften him up, and then go for one of his famous leg locks. I know Fedor comes from a Sambo background, but I think the way to submit him would be with a leg lock.
Of course there is always the problem of Barnett's cardio, and Fedor not being human and all. I'd say Barnett via Kneebar late in round 1.