Cain Velasquez' domination of Brock Lesnar in UFC 121 suggests that the new heavyweight champ could hold the belt for a long, long time. There hasn't been a heavyweight with a skill set this well-rounded since Fedor Emelianenko.
Opinions differ on what stage Fedor's career is at right now, but it's obvious that he dominated the past decade, racking up 27 straight victories before falling to Fabricio Werdum's triangle choke. Fedor's grappling and striking were equally feared, and more than anyone else he didn't flinch when caught in a bad situation.
Velasquez has showed the same skills and fearlessness. He outgrappled Lesnar as well as outpunched him, and when taken down he quickly got to his feet. He didn't hesitate to trade blows with the UFC champ and Lesnar's size didn't bother him at all.
In other words, he fought a lot like Fedor fights. But he also looked quicker than Emelianenko, and less prone to sloppy fighting than The Last Emperor. Could he be better than Fedor? It's possible.
Over the last few years a Lesnar-Fedor matchup was on everyone's mind, and this fight is pretty much how I imagined it would go. Lesnar has improved a lot over the last few years but he still was no technical master. His vaunted grappling prowess—national wrestling championships and all—is more from just being a freakishly huge monster than having the best ability (he has the best ability of all the monsters, and is the biggest monster to boot). So it was only a matter of time before someone truly exposed Lesnar; the problem was that most of the heavyweights available were one-dimensional.
Velasquez punched as well as Carwin and grappled better than Lesnar, with Fedor's fearlessness and unflappability, and he's faster than all of them. That's a recipe for a long career. Normally when a fighter makes a splash and starts off 10-0 or so, it's just a matter of time before his first loss, after which he becomes the typical fighter—wins a few, lose one or two, win a few more. Velasquez might be among the rare exceptions, of which Fedor is the only one so far at heavyweight.
Just as we may never see Fedor vs. Lesnar, we may never see Fedor vs. Velasquez. If we do, it will probably be at least a few years from now, and with Cain only 28 currently, by the time they square off it could be a passing of the torch, from the Last Emperor to the Next One.