First of all, I was always more of a Marvel fan growing up. If you're going to hold that against me then you should probably stop reading now and save yourself the frustration.
I was never a huge batman fan as a kid. Knowing he has no powers kind of made him boring to me. As I got older i could appreciate the character more and more. This is a man that has it all; money, women, genius-level IQ, and yet risks it every night due to the dark side of himself. Trying to save others by stopping criminals all based on what he witnessed as a boy. Watching your parents be murdered would have a profound effect on any of us.
As i was re-watching Batman Begins last night, I did not feel the same sense of Jekyl and Hyde character the comic Batman seems to have. Charming billionaire playboy by day, merciless justice dealing vigilante at night. The line in the movie seemed so blurred together.
There is also almost no sign of any sort of high IQ, let alone a genius detective throughout the franchise. When he is recovering from Scarecrows poison, Lucious Fox explains the biological weapon he was attacked with. Wayne replies, "Am I supposed to understand any of that?". I would assume the comic version Batman would be able to not only understand but cure himself.
Now I enjoyed the Batman Trilogy, but I don't think change is crazy. I HATE the choice of Afflek for Batman as well, but I believe that, given the correct writers, he will pull it off.
Bat-Flek will have to be written as a genius just to be on par with some of the super heroes that are rumored to be in this upcoming Batman/Superman sequel. Hopefully we will hear more details confirming this and the public (including myself) will give Afflek's Batman a shot.