This was revealed via Nintendo’s NPD statement. Ubisoft must be pleased with this development after third party games used to fare so badly on the Wii. There have been 8 other games that have achieved this feat in the US for Nintendo platforms, according to Nintendo.
They were, Wii Play, Wii Fit, Wii Fit Plus, New Super Mario Bros. Wii, Mario Kart Wii, Super Smash Bros. Brawl and Wii Sports Resort. The game sold 120,000 units in July, which was revealed by NPD.