I don't buy anecdotal evidence like RE4 Wii. It was a $30 budget port of one of the biggest games of last gen (franchise/hype/review) on one of the fastest selling platforms ever. Nintendo has cultivated an audience - through their own releases, console features, online infrastructure etc. that isn't conducive to stuff like CoD, FIFA, Witcher etc. Yes, there is a small number of core fans that wants everything on a Nintendo platform, but that's exactly it - they're tiny in number. Even if the games had feature parity, I don't think they'd do anywhere near as well as the other systems. Software feature parity isn't the same as online infrastructure parity. They'll be lacking in some way or other. Even if everything was on par, it just doesn't make financial sense because of the audience. Sorry, but it just doesn't. These devs would be better off making a game that might appeal to the Nintendo crowd. It'd be money better spent.
Heh, what is the "Nintendo crowd"? Kiddie games? Cute games with fuzzy characters? Heh, Monster Hunter Tri sold over a million on the Wii. Call of Duty Modern Warfare Reflex sold well, too. Thing is, these games can sell well if they're treated properly and marketed as well as the other versions.