The problem with this, is that while the Wii was supply constrained in the beginning. the Ps2 wasn't, because it had 5 or so months only in Japan, making it have enough supply for that.
The DS had the same situation as the Wii and was supply constrained for a long time.
Look at how it took off compared to the Ps2. http://vgchartz.com/hwlaunch.php?cons1=Wii®1=Japan&cons2=DS®2=Japan&cons3=PS2®3=Japan&weeks=300
The Ps2 started out a lot faster than Wii, but the Wii has just recently become less supply constrained, and the Ps2 lost some of its momentum in Japan over time.
Still, I think it will be fairly close. Wii will be within 5M of it, either above or belove.
http://www.vgchartz.com/games/userreviewdisp.php?id=261
That is VGChartz LONGEST review. And it's NOT Cute Kitten DS
