It's too early to tell.
Honestly, I'd have to watch Norton, Roth, and Tyler, before actually judging...Though, I do agree that Norton is a much more inspired casting choice for Banner. I'm looking forward to his performance, and see him bringing a lot of justice to the character, with what's been described so far. Especially when it'll come down to both he and Roth face to face on screen. Roth, IMO, is the perfect choice for Blonsky. So looking forward to that as well.
Tyler as Betty...She may be a good replacement for Connelly. We'll see.