Let's be honest about something:
Cain may be of Mexican heritage, but he's not a Mexican. The HW belt is in the US as of tonight...
That said, I'd disagree with the OP entirely.
At the of 2013:
HW: Overeem
LHW: Still Jones
MW: Still Anderson, srsly don't know who the hell you expect to come take this belt. Lombard has potential, in theory, but I think he's way too short/brawler-esque to really be a danger to Anderson.
WW: There's a very small chance Hendricks takes it from GSP, at which point I see Rory becoming the champ or GSP winning it back in a rematch. That belt is staying at tri-star with GSP or Rory. I'd put a slim chance of Maia holding it, if he can get it from Rory (meaning GSP loses to Diaz, then Rory beats Diaz down)
LW: Bendo, maybe Pettis, but I think Bendo has improved more since the first fight
Featherweight: Aldo is going to beat Edgar, badly... And Aldo's p4p stock will climb.
Bantamweight: Renan Barao beats Cruz when Cruz comes back too early from injury. Cruz gets re injured, and is never the same fighter.
Flyweight: All 4 of the flyweights from the tourney are capable of holding that belt.
Womens: Ronda Rousey via lack of credible talent/competition