Even though he doesn't lead in WAR, I think it's Braun but I could see Upton or Tulo too, maybe Kemp. Not Victorino. This race could be one of the closest races of the awards that we say we don't care about but get all upset when someone makes a case for someone that we don't think deserves it and get all pissy when the guy we think should have won doesn't win; See MVP, 1999, Pedro.
I think it'll be Upton, Kemp, or Braun. It's too tight to tell right now, there's no clear deserving winner, although Victorino deserves to be up there with the top group but probably won't be considered because he doesn't have a lot of power and is a bit short on counting stats since he missed a bit of time. It's pretty impressive that he's leading in WAR despite playing 30 less games than Kemp/Upton/Braun. But again... he won't be considered. He's not the prototypical MVP.