I have a hard time seeing this game selling less than 20 million lifetime. With numbers like that it must push harware. Not in the immediate Halo 3 way, but in the gradual word of mouth way like Wii Sports, or Wii Fit, or pretty much any of the big Nintendo games this generation. Bundles would give and initial hardawre boost though, especially if they have a special colour.
"Now, a fun game should always be easy to understand - you should be able to take one look at it and know what you have to do straight away. It should be so well constructed that you can tell at a glance what your goal is and, even if you don’t succeed, you’ll blame yourself rather than the game. Moreover, the people standing around watching the game have also got to be able to enjoy it." - Shiggy
A Koopa's Revenge II gameplay video