Oh come on! If Pixar made a 2 version of Toy Story, or the Incredibles or... one the CGI version we all know and the other a traditional hand drawn cartoon d'ya think movie reviewers would have rated them independently? Or do you think movie reviewers would have compared the CGI version with the hand-drawn version and rated them relative to each other?
My vote is most movie reviewers would rate 2 versions of the same movie relative to each other. And movie re-makes get the same treatment. So don't go all boo hoo not fair to down rate Wii version because it's visuals don't stack up to the PS360 version. Nintendo made the choice to have low-fi graphics power, and for games that rely on graphics as much or more so than gameplay for gamer attraction marking down the Wii version is legit.
The experience of MW3 on Wii is not as good as the experience on PS360. That's the revewer's opinion and it's right to score the Wii version lower as a result. 4.5/10 does seem a tad harsh though, but some of the criticisms aren't strictly about the non-HDness.
“The fundamental cause of the trouble is that in the modern world the stupid are cocksure while the intelligent are full of doubt.” - Bertrand Russell
"When the power of love overcomes the love of power, the world will know peace."
Jimi Hendrix