I see your point about why he would keep his accent. He does seem to have a very good work ethic. In interviews, Bale seems more concerned about his craft and his character than himself, unlike Cruise and other ego-maniacal Hollywood stars.
Ok, that sounds great. So the only movie you will see this summer and from here on out is Batman Begins and anything that has Bale in it. But be careful because tom cruise is engaged to Katie Holmes so might want to re-think batman.