Big let down. I got tired of all the hype it was getting. I mean I love Halo. I enjoyed the story in Halo, but not so much in halo2 or 3. Multiplayer was good in Halo, great in halo2, but in Halo3 not really much different. I wasn't expecting them to change the controls or anything (if it isn't broke don't fix it), but people give it more credit than it deserves IMO. I was really impressed with the graphics though.
I can tell you one thing though, Halo3 is sitting in my living room gathering dust.