This has been a great year for really good games.
Of those that I've played, a few have really stood out to me as excellent: Halo3, Bioshock, Mass Effect and The Witcher.
Halo 3 was predictable and generally lacked a whole lot of innovation in gameplay over the previous entries in the series, but it didn't intend to do those things, either. It is a very well done incremental polishing of the formula used for the preceding entries in the series. The level design is well done, and the storyline plays out at a reasonable pace to keep me interested. While not my pick for Game of the Year, it is a very enjoyable game and well worth my time and money.
Bioshock was wonderfully surreal. I absolutely love the progressive unveiling of what's really going on. The overall look and feel of the game is polished to a level that is almost unnerving. The underlying basis of objectivism and all that goes with it plays into the storyline wonderfully and enhanced the overall experience superbly. There are a few moments towards the end of the game where I felt the level design was lacking the polish of some of the early and mid-game content. The fundamental gameplay is good, but nothing spectacular. The best strengths of the game are in its storytelling and immersion into a depressing juxtaposition of a dystopian world sprung from a utopian vision gone wrong. Many criticise Bioshock for being derivative of System Shock 2. Perhaps that's a true statement. To me, it doesn't matter one bit. I'm not trying to decide if Bioshock is better or worse than SS2 or if it innovates or derives in comparison. I'm deciding whether Bioshock is a well crafted and enjoyable game. It is.
Mass Effect is a later entry in the foray, and highly anticipated. It lives up to the hype. The main storyline missions are well designed, and well integrated into the story. The basic gameplay elements are simple, but not simplistic, and give just enough of a challenge to my twitch reflexes to keep me from being too complacent. I was totally sucked in to the story and the world, doing everything I could to find every tidbit of dialog and side content available. While not without flaws, I very much enjoyed Mass Effect, and it's likely I'll be back for a 3rd playthough at some point.
Even against those wonderful games, my pick for Game of the Year has to go to an unexpected (at least for me) game called The Witcher. I picked it up based on the terse but strongly voiced recommendation of Scott Jennings. I shudder to think that I almost missed this game. The gameplay is well done and well balanced. The look and feel are polished and smooth. The world and storyline have incredible depth. Somehow, the designers have woven a remarkable tapestry where everything all comes together. Characters I care about. Choices that tug at my conscience (and have a real effect on the ensuing story!). Wow.
The Witcher. Absolutely wonderful and easily my top pick for Game of the Year.