I could give it to Christian Bale for the simple reason based onthe fact that he plays a character who has a duo personality, one in which Bruce Wayne is a playboy, and the other is that of Batman in which he has less to say and usually what he says he is very low key as not to let anyone know who he really is. Yes, Heath Ledger did a good job as the Joker, but sometimes one thinks of a serial killer and you begin to wonder as to why would we give an award to someone like that. Just an opinion. Maybe the award will be split: One for a living person such as Christian, and the other posthumesly for Ledger.
Joseph