2007 was a pretty great year, first full year of Xbox 360, PS3 and Wii on the market and the quality definitely jumped up from what we got in 2006. My faves would be...
1. Super Mario Galaxy - Still my favorite 3D Mario game and one of the most creative games I ever played.
2. Mass Effect - I actually didn't like it much when it came out. Years later I was prodded into trying ME2 and fell in love with the series. Went back to play ME1 and while it definitely has some gameplay issues, it's still a great narrative introduction to the series.
3. Bioshock - Brilliant narrative concepts wrapped up in a great first-person action game.