Christian Bale was my favorite Batman because those were the best Batman movies ever made. They treated the story with some seriousness. Director Tom Burton gave the series a whimsical, deranged fairytale vibe that was interesting, but not nearly as good. I say we give Ben Affleck a chance. It's all going to hinge on this -- whether Affleck can do the 'gravelly voice' thing for Batman without making me laugh. Bale was able to do it, but only just barely.
Affleck, in my opinion, is a better director than actor -- but who knows, maybe he'll prove us all wrong.
Best quote from
Gigli, back when Affleck was dating Jennifer Lopez:
Lopes: (husky voice) "It's turkey time.
Gobble-gobble."
EDIT: My take on the various Bat men.
Adam West: The No-Muscle-Tone Batman. At least he blandished children into brushing their stupid, grimy teeth.
Michael Keaton: One of the better Batmen -- he was probably the second or third best actor in that role. Keaton was able to pull off the hauntedness of the role better than nearly anyone else. He managed to look a little bit mentally unbalanced, which ... well, it makes sense for the character.
Val Kilmer: I poop on you, Val Kilmer. As mentioned earlier, he's a pretty boy, and not much else.
George Clooney: Now we're just slumming. Clooney makes for a good Bruce Wayne, billionaire playboy, which isn't much of an acting stretch. When he was Batman, life was sad and unappealing. Instead of cheering for him, his performance made me feel sort of sad, and ache-y.
Christian Bale: The best Batman to date, but I think he benefitted from a great series of scripts, too. A great actor to begin with, he made the role believable.