I'm in Europe at the moment, so...
1. Halo 3
2. Mass Effect
3. Crackdown
4. BioShock
5. PGR4
6. Alien Hominid HD
7. Lost Planet (again, I'm in Europe, and it came out in January up here)
8. Portal (The Orange Box then)
9. Naruto: Rise Of A Nnja
10. Earth Defense Force 2017
I swear, the decision was so damn hard to make between Halo 3 and Mass Effect that if I could, I'd give them a tie, really... both are unbelievably good, and feel like they were made for me...
As for the rest of my list, never was it so easily to drop about 10 sure-fire GOTY contenders, and these don't even include other sure-fire GOTY contenders like COD4 and VF5, which I didn't include on the list because I don't own them - yet. The Orange Box is only on there because I played through Portal by a friend, and thought it was too good to not mention...
What an amazing year 2007 is...