I pre-ordered it for DH and went out early in the morning to get it, becuase he wanted it so bad. He still hasn't played it!!!
Finished it 2 days after it came out on Legendary, it is a great game. Been going through the game looking for the skulls and terminals now. I am glad that Halo 3 is a great game, Halo 2 was a real dissappointment. Halo 1 was great too. I definately reccommend playing Halo 1 first, then 2, then 3. If you play 3 without playing 1 and 2, you will be missing out on the story, and unable to fully appreciate Halo 3 especially imo.