They should be evry very close and as such any one of the three could end up ahead. Thats if we take the vgc numbers as correct. The supply of each of the three was similar. Therefore my wild, wild guess is:
360 - 1.7m
Wii - 1.8m
PS3 - 1.8m
Using VGC numbers:
If Wii ships less than 1.65m, that will mean it is in negative supply.
If PS3 ships less than 1.1m then it would be in negative supply.
If 360 ships less than 1.1m then it would be innegative supply.