Absolutely terrible!
I can honestly say I should have definately left it in the shops and on the shelve.
I attempted trying to enjoy it for about 5 days on and off yet even about five or six levels in I was left wondering when the boring "walk along, shoot a few people. walk a bit more, shoot a few more people" would stop and something would make me go "yeah! now this is fun". That's the problem; This game is about five years (if not more) behind everything other 1st person shooter in terms of imagination. There is absolutely nothing that got my heart racing apart from I had paid £50 for it. My only saving grace is that I took it back and got a refund.
Verdict: Possily the worst game on the 360 (including Xbox Arcade)