CVG says that Halo 3 doesn't mess with success:

Halo 3 is the gaming equivalent of a Hollywood blockbuster. It's not going to revolutionise the genre - it's not meant to - it's meant to be great fun, which it is. Never lose sight of that. The visuals, guns, vehicles, enemies, set-pieces, musical score... they've all been cranked up to 11 to create an experience up there with the best sci-fi properties.

They gave the game 9.7 out of 10.