Mass Effect will probably win RPG of the year, and possibly GOTY.
If not ME, I think GTAIV will, as it's done very well for GOTY honors. SMG and SSBB will probably launch too late to get any solid honors, unless SMG is so vastly superior that they make the GOTY honors that late this year.
Either way, top 5 should have:
GTAIV
ME
H3
SMG
GOW2
Back from the dead, I'm afraid.