On the one hand, yeah, Daredevil.
On the other hand, Daredevil is a film from 2003, two years before Nolan changed how people think about superhero films with Batman Begins, five years before The Dark Knight, five years before the superhero craze really kicked off with Iron Man, and at least five years before Kevin Feige (the brains behind Marvel's film franchises) realised that Marvel could cash in on Iron Man's success and make serious comic book films, rather than the mostly camp and tongue-in-cheek stuff that had been released up to that point.
Despite the couple of flops that everyone seems to associate him with, Ben Affleck is actually a fairly decent actor, with some good films under his belt. It's a strange choice, and I can't yet picture him all suited up, but he might surprise us.
Who honestly thought that Heath Ledger as the Joker was good casting when it was announced? Or that funny-man Michael Keaton would make a good caped crusader?
At the end of the day, however Affleck turns out as Batman, he can't do as bad a job as Clooney.
EDIT: Aww man! Ninja'd by Mouse.