I'm cautiously optimistic. If this were the pre-Gone Baby Gone
Affleck I might be a little worried, but Affleck's done a lot to reinvent himself since the earlier part of his career. I actually didn't think he was all that bad as Matt Murdock, it was just most of the rest of the movie that fell flat. I'm still having a hard time picturing him as Batman, but I do think he'll at least be an excellent Bruce Wayne. I'll wait until I see him in the costume and delivering some dialogue before I pass any further judgment.