While it was released for mobile devices last year, it didn't hit PCs till this year, so I've gotta say my GotY so far is Superbrothers: Sword and Sworcery EP. Admittedly, the only other games I've played this year that were actually released in 2012 are Journey, Alan Wake's American Nightmare, Solar 2, and Penny Arcade's Rain-Slick 3. They're all fine games and worth playing (especially since they're all cut-price offerings), though. And Superbrothers is a great game in its own right, with great writing and one of the best soundtracks it has ever been my pleasure to hear.