The game was released in both Japan and North America; sales on the first day in Japan alone reached 480,000 copies.
Sales for North America have yet to be released, but it would be safe to assume the game is well on its way to a million copies purely based on first day sales. This game is Mario's first new game on Nintendo's latest handheld and paves the way for his next outing on the forthcoming Wii in Super Mario Galaxy.
That's an incredible amount of copies sold, and it beats all other portable Mario games. Nintendo doesn't seem to be able to make any wrong moves at the moment and seems to be dominating the mobile gaming sector.