Across all platforms, the unequivocable choice should be Steel Battalion. No other game this year has even come close to enhancing our idea of gaming like this game. The immersiveness of this game is a really difficult thing to understand until you get it in front of you with a decent HT setup. You are piloting a giant walking tank, and there is absolutely nothing to break the illusion of that. I'm seriously considering going out and getting a pilots helmet when I play it (when I have time) because it just feels right. Of course with most web community types being lemmings, its likely to be some other massively overhyped retread of a retread, and I feel its a shame that such a watershed game won't get recognized.
I'm really thankful that its moving as many units in the US as it is (from my own information) because I think it inspires developers to make edgy games with radical concepts, and assure publishers that they can be successful in the market if they are properly realised. I think when the Xbox project was started, this is the type of content that the Xbox guys really wanted to see, this is the kind of game the really creative developers always wanted to make, and depending on how it does sets a wonderful precedent for the future.
Just to pre-empt the inevitable babble, if you havent played Steel Battalion yet, you should. If you are going to post something denigrating about the game, when its obvious you have not played it, you are an idiot.
