Didn't they said that they should have 1.8M by start of fiscal? I thought so. And isn't Fiscal Year at 31st March? Maybe all factories haven't started up or something.
I don't see a lot of other solutions.
http://www.vgchartz.com/games/userreviewdisp.php?id=261
That is VGChartz LONGEST review. And it's NOT Cute Kitten DS