I think Nintendo, but also Sony and Microsoft will have a hard time convincing people to buy a console or portable once Apple releases iOS 7 with the rumored game controller support. You can be sure controllers will be made available for other popular phones too and in about a year there'll be plenty of good games on the market, for much less than classic console and portable games.
If you can get such a controller for less than 50$ and already have a smartphone or iPod touch like device, then I just don't see why you'd want to buy yet another gaming device.
Now give me a good and comfortable controller for my iPad and I won't buy any console anymore.
GTA / Madden | Fifa / CoD | Battlefield / Mario-like platformers are on iOS right now. Most of them quite decent. They'll get better if an official Controller (or) an API is launched. I think there's an opportunity for a proper platformer IP exclusively made for mobile seeing as how its exploding onto traditional consoles (Ouya/etc)
Remember Nintendo's investors threatened the board and wanted them to release Nintendo IP on Mobile appstores .