2.2M production (stockpilling taken into account).
45% of the sales would then be in America. Up untill now, it has had 44%.
This is far from impossible. If they do 2.3M (lower stockpilling needed than I expect), this will mean 43.4% is all it needs.
Fair prediction. A bit high, but totally fair.
http://www.vgchartz.com/games/userreviewdisp.php?id=261
That is VGChartz LONGEST review. And it's NOT Cute Kitten DS