1)Skyrim
2)Batman: Arkham City
3)Deus Ex: Human Revolution
I was expecting to put Assassin's Creed Revelations in there, but I don't know what the hell happenned. It does everything the previous ones did and imporves in a lot of areas, and Assassin's Creed is my favourite franchise ever. But for some reason, I didn't enjoy it as much as 2 and Brotherhood. My guess is that's because it's starting to repeat itself now, and because they have adopted the Call of Duty style of releasing a new one every single year, without giving any breathing room for me to miss them.
Also, I'd like to give a honorable mention to Sonic Generations, because it's the first Sonic game in a looooooooong time that I thought was really good (I don't have a Wii and therefore didn't play Sonic Colors). It was really short though.