TWRoO on 26 September 2008
Wii Fit depends on supply.
So while I can't be accurate (not knowing how much supply Nintendo has for Christmas) I think Wii Fit will pass GTAIV in mid December, but due to launching in Japan in 2007, it will just miss out on outselling it for 2008.
Mario Kart I think as a chance to pass GTAIV this year, but I am expecting the first or second week of January instead.
