The best point for comparison would really probably be simultaneous multiplatform titles. The only platformers I can think of in that regard are probably Sonic Unleashed, Sonic 4 Episode I, Mega Man 9 and Mega Man 10, which all sold best on Wii afaik. de Blob 2 will be the next real point for comparison. Bonk BOE also, though DD sales are harder to come by.
I'd say this also works for any genre, comparing different titles (even within the same brand) can skew the results otherwise. A good example would be Goldeneye versus Blood Stone... looking purely at the genre and brand, you could make the argument FPS sell better on Wii than HD based off that, which I'd say is dramatically far from the reality of things. Black Ops I'd say would make for a far better example.
