I agree with the OP, when I first looked at the year in review, I knew that Portal 2, Mortal Kombat, Skyrim, Uncharted, Batman: Arkham City, and Skyward Sword were going to be awesome, but the true GOTY contenders were yet to be determined.
Upon further thought, I acknowledged Skyrim as the probable GOTY. Further ponderings later, I admitted that Uncharted 3 has a pretty solid shot at taking down The Elder Scrolls. The 10/10 review GameInformer gave Arkham City drove me to buy it at the midnight launch and play it nonstop in all my freetime when I'm not at school, lifting, acting, or posting on The Escapist Forums.
As such, I believe the OP is correct, Arkham City, Skyrim, and Uncharted 3 are in the running for GOTY, not much else as far as I can see it can unseat them. An FPS hasn't won GOTY since Halo 2/ Half-Life 2 in '04, so no Battlefield 3/Rage/Hard Reset/Modern Warfare 3/Bulletstorm, so none of the huge amount of FPS' released this year will get any recognition save Battlefield 3's probable "Best Shooter" and "Best Multiplayer" awards.
While Skyrim has the most chance to take GOTY, there is one other foe that could unseat this ages-old RPG franchise's most recent release. I'm talking of course, about the last cry from the Wii before it dies, The Legend of Zelda: Skyward Sword. TLoZ has always been a fantastic series, and while some entries get hate for various reasons, they're usually minor when compared to the overall genius of the franchise. Twilight Princess was also the only game to be a legitimate competitor against Oblivion back in '06's GOTY.
This year has some great games lined up for GOTY, but nothing beats last year's "Represent Fest". You know what I'm talking about.
Mass Effect 2 for the 360, God of War 3 for the PS3, Starcraft 2 for the PC, Mario Galaxy 2 for the Wii, but they all fell under the dusty boot of the multi-platform Red Dead Redemption... that was awesome.
-Chillz