Well the games that have some chances to be 2008 GOTY are:
PC:
Dragon Age
Empire: Total War
SPORE
Starcraft II
Warhammer Online
PS3:
Little Big Planet
Metal Gear Solid 4
Xbox 360:
Fable 2
Gears of War 2
Ninja Gaiden 2
Wii:
Mario Kart Wii
Super Smash Bros. Brawl
Multiplatform:
Alan Wake
Fallout 3
GTA IV
Mafia 2
RAGE
Order By Probability of being GOTY:
1º SPORE
2º Starcraft II
3º Super Smash Bros. Brawl
4º GTA IV
5º Metal Gear Solid 4
6º Alan Wake
7º RAGE
8º Dragon Age
9º Mafia 2
10º Little Big Planet
...