The Walking Dead for me. It probably wouldn't have been my GOTY in a different year, but like others have said there weren't as many standout titles for me this year. I loved that game though and I think it's deserved all the praise it's gotten.
After that it's probably Halo 4. Not sure about the order of the rest of my top games yet.
P.S. people that chose ME3 are you sure you didn't misread the thread as most disappointing game?