Wii.qj.net has posted this artical about wii play i think
Nintendo may not have the most technologically powerful home console in this generation, but they are definitely top dog when it comes to sales. In North America, the company has not one, not two, but three games in the decade's top five best selling games list.
Headlining the list is Wii Play, which according to NPD sales data has so far moved 11.1 million copies in North America since its launch in April 2008. That number doesn't even include copies sold as part of a Wii bundle.
Coming in at a distant second is Rockstar's Grand Theft Auto: San Andreas with 8.25 million sales, setting up a seesawing pattern between Rockstar and Nintendo. Wii Fit is at third with 7.9 million sales, at fourth is Grand Theft Auto: Vice City's 6.9 million sales, and Mario Kart Wii brings up the rear with 6.7 million units sold.[/QUO
This was number one for one reason. The wiimote that came with it!! lol