I think its an absolutely fantastic game. I haven't tried firefight yet, but I am about 3/4 of the way done with the campaign.
Positives.
1. Single player campaign is one of the best Halo campaigns that I have played yet, its perfectly paced, and can be very moody at times.
2. The addition of multiplayer medals during campaign is nothing short of brilliant, and brings the replayability up a whole lot.
3. The new pistol and silenced SMG are a blast to use, and I like how alot of the covenant have personal shields (reminds me of the good old days of fighting elites)
4. The music in this game is probably the best I have heard from a Halo yet.
5. Having the ability to finally unlock the most coveted Halo 3 armor (Recon) is pretty sweet.
6. Bungie's detailed stat system for ODST, so you can see how dominate you are!
7. The new visor view mode is a really awesome addition.
8. The achievements have a perfect balance of easy-hard.
Neutral.
1. I honestly still feel like a spartan in ODST, not much of a change at all imo.
Negative
1. Graphics are definitely a step below Halo 3
2. Its a rather glitchy game, and the frame rate does stutter sometimes (not horribly so, but enough for you to notice)
3. No BR is a bad thing in my book (was by far my favorite weapon from Halo 2 &3)
4. There is no matchmaking for firefight.
5. The human AI is still stupid as ever (but at least they are funny)
That about sums up what I think about the game. I'd give it a score of 8.75
