Dark Souls - Perfect mix of skill needed, frustration and that warm, happy feeling that ensues after you do something badass. It's also pretty, I guess. As long as the graphics don't negatively effect gameplay, they are usually at the bottom of the list of what I think a game needs...
Deus Ex: HR - I mean... Really. It's a Deus Ex game. And the title mentions neither invisibility nor wars.
Arkham City - Although I haven't played it yet, given the reviews this thing has managed thus far, it is probably a strong contender.
No Skyrim, you may wonder? First, it hasn't even come out yet and hype alone doesn't make GOTY material. Secondly, I haven't enjoyed a Bethesda title since Morrowind.