I can't speak to it's multiplayer as it isn't really my cup of tea but Halo 3's campaign alone is a blast, if ever so slightly too short in my opinion, though at least that helps it avoid padding. The suite of weapons is more refined from Halo 2's which is both a compliment and a complaint as I enjoyed how broken certain dual wielding combos were in that game. There's still plenty of weapons that shine in this title though.

I think for my money, it's probably the best game in the series, not my favorite, but a very refined, gorgeous, and iconic game.