Djokovic is probably the best hardcourt player in the world. Nadal certainly could beat him, but Novak shouldn't be a +160 dog.
As for Blake, that guy is too inconsistent. Gonzalez can definitely beat him, especially since Blake is coming off an emotional win against Roger. I know the public wants to see the American Blake against the world number one Nadal, but I like the chances of those two facing off for the bronze, not the gold.