KFM.com, a website devoted to the martial art known as the Keysi Fighting Method, or KFM, has stated that KFM is the fighting style which is primarily used by Christian Bale in Batman Begins, and will also be featured in The Dark Knight.
Bale had this to say about the martial art:
We've gone a bit further with Keysi (...). I'm actually learning how to do it more realistically than ever before, though it's such an extreme way of fighting; there are literally moves where you tear someone's cheek away from their face, or rip their nose off - every part of you becomes a weapon. It's formidable. Batman doesn't kill, so we can't have him doing that; we modify it.
KFM was also featured in Mission: Impossible III.