I'd go with Ed Norton.
I liked Bale in American Psycho, but that movie had brilliant script to fall back on. Liked him in The Fighter, too, but I wouldn't consider either role seminal.
Ed Norton impacted the entire industry with his acting style in American History X and 25th Hour, and he was awesome in Fight Club. And he's been taking roles all across the spectrum.
That being said, I haven't seen either guy do much out of the ordinary the last decade or so. Guess Bale might be fresher in that respect- at least his claim to fame isn't based on a span of three years around the Y2K mark.