The wii didnt had that many good games this year, it won the year for me with Donkey Kong though :)
IGN is biased fo "hardcore" games, Wii had a lot of "hardcore" games this year compared to the other years. Hence, IGN considers the Wii to be slightly better
On the other hand, if you check PART 2 youll notice how biased they are for PS360, they actually gave party games category to the 360, which is just laughable they actually make a bunch of rediculous categories just to make the Wii look smaller (Third person shooter, third person action, action, action/adventure, first person shooter) on the other hand they call any friendly a a family game (which probably means something like games for retardeds or something to them)
Conclusion: IGN still sucks
Nintendo is the best videogames company ever!