User blog comment:Drkdragonz66/Modern Warfare 3 will apparently not be released on Wii/@comment-24.151.68.110-20110521204400/@comment-252163-20110522222045

Perhaps IW doesn't consider the Wii to be a real system, but Treyarch does. It must if it's willing to take on the burden of making a Wii version of one game while making an entirely new one.