After extensive playtime with both the PS3 and Wii versions of Call of Duty: Modern Warfare 3, I have to give some solid commendations to the team at Treyarch for the Wii version.
Even though the visuals have suffered a fair amount, the gameplay is largely the same across all platforms. It is particularly impressive that the Wii can deliver the same single-player campaign experience. Infinity Ward's position that the Wii could not deliver the same experience is obviously false and a testament to either their inability or Treyarch's superiority.
I will, however, give a rather disapproving finger wagging to developers that continue to use such a low gamma setting. I understand most people put their TVs on Vivid or Sports settings and never bother to properly calibrate their set but it's a bit frustrating for those of us that do to have to make those changes every time we want to play a game. Brighten those levels up!
I also find it curious that the Wii version is quite a bit harder than the other versions. Enemies take much less damage than they do on the higher resolution versions. Even with added precision of the Wii remote, I found myself having to squeeze the trigger at least twice to take down a similar enemy.
In conclusion, the game has an enjoyable campaign mode and I would recommended at least a single playthrough. It's a loud, twisting roller coaster on all the platforms. Highly recommended in regards to the single player content.