Oustanding follow through!
Sound: Marty outdid himself. The musical score does sound like the "Return of the King" that he was aiming for. Very super-hero-esque. I was whole-ly impressed. The sounds of the weapons as well as the ambient sound effects and character voices were richly cast.
Gameplay: Back to Halo: CE. It was maneuverable on Legendary single player if you had played it through a couple of times and so is Halo 3. Although, with the addition of 4 player co-op as well as a continually fantastic online multiplayer experience, gameplay is a solid win. It really is the same Halo gameplay improved. There isn't too much new innovation but Halo doesn't need it to win. Not every new game in series needs a brand new style for the win. I wasn't really a fan of Halo 2's online multiplayer. I thought it was imbalanced and more frustrating than fun. Halo 3 seemed to have fixed most of my complaints about Halo 2 for this topic.
Story: Although there was little character development the story arc was sealed (with enough hope in the end for the main character). I thought there was enough development in the previous two games with not enough end-game torque. Halo 3 fixes this and left me edified but wanting more. Unless you've set your standards far too high or you don't know how to review objectively you will probably find something similar.
Tilt: I had so much fun playing this game and look forward to playing it for a while to come - it's hard to tilt lower than it's worth.
10 all the way.