I'm not a Lesnar fan at all, but he is going to be tough to beat. Not because he is a great fighter, but because the HW division at the UFC is pretty weak. Heck, Frank Mir is probably a bigger fraud than Lesnar.
Carwin will probably get demolished again Lesnar at UFC 106. Although Carwin showed a good chin against Gonzaga last fight, he was in deep trouble before landing a nice punch. I haven't watched the Velasquez fight from Saturday, but he too didn't look all that great against Kongo last time. Randy is too old to put up a nice fight against Lesnar and Junior dos Santos probably needs another fight or two before getting a title shot. Maybe Big Nog could beat Lesnar, but I don't know.