I feel like this year is going to be a lot more satisfying in terms of quality titles in Q3-Q4.
Maybe its because I'm actually going to be able to afford them before they are in the bargain bin?
Seriously though. Assassins Creed I had amazing expectations for when I saw that first trailer of it at Sony's E3. Combined with no money, the reviews saying it was repetitive and short kept me from buying it to this day (I plan on picking it up soon). Mass Effect, ever since I saw that first trailer on the Marketplace where the main character is talking to an alien in a bar and I saw the character models. Then came the reviews saying framerate problems and other annoyances. It just didn't seem like a must have. Halo 3 was fun but the multiplayer just didn't shine like it did during Halo 2.
Bioshock and Halo 3 were my only 1st day non-sport purchases of 2007.
In terms of non sports... Brother in Arms Hells Highway has tons of development time: the gameplay looks rock solid and the graphics look stunning, Legendary looks like something fresh with its pandora's box premise and its solid gameplay, Far Cry 2 looks polished too and the series has always had fun gameplay, Velvet Assassin also looks fresh and everything about it looks interesting, for me Banjo Kazooie looks great, Gears 2 no comment it will be amazing, Left 4 Dead looks sick and I love how co-op is so important, Mirror's Edge looks fresh too, and Dead Space looks new and interesting.
I think 2008 will bring a lot of quality titles to the Xbox 360.