OU's defense is not a factor. However, they're offense is so good that WVU's defense may not matter, either. I want to think that Texas' defense demonstrated how to stonewall OU's offense - provided you have sufficient athletes, but Texas had OU's TE/FB guy Constanza or Kamoze or whatever his name is out of the game.
Realistically, this is a pick 'em. History says that an random helmet on ball fumble or tipped pass will upset the house of cards one way or the other.