Wii is not being driven by Wii Party, Kirby, Epic Mickey, DKCR, Just Dance, Michael Jackson, etc. It is being driven by reputation and value of bundles. Move and Kinect still gaining a following for motion control while Wii is firmly established. Some of the shoppers (a lot of them) know Wii is a safe choice. It will take word of mouth or just plain stumbling across Move or Kinect before these people would think otherwise. These incredibly casual shoppers are also the ones that pick up the Wii software that is at the checkout lanes selling for $10-$20 per title.
Its libraries that sell systems not a single game.