Where I once saw kids play Mario on a Nintendo DS, today I see kids play Minecraft of iPads.
Apple crushed Nintendo by creating iOS devices and opening up it's platform to indie devs for a minimal fee. If I wanted to start coding for Nintendo.... how would I do it, and how much would I have to pay in licensing? I have no idea, and I wouldn't know where to look.
It would seem easier to go for the tablet ecosystem that most people have and is more easily accessible. I think not only did Apple destroy the Nintendo casual market with iOS devices, but also through leeching potential developers.
Also, if I were Nintendo, I would be grovelling to get Mojang to port Minecraft over (Mojang says that they're "too busy"). So far..... nothing... and it's so stupid as to why not because the game is really something Nintendo should have been able to create, and it's a perfect fit for the system. It's just a shame too that with all Nintendo's game dev talent, this something as much fun hasn't eventuated from them, and it's been Mario after Zelda after Donkey Kong.
Nintendo is also locked itself out of the hardcore market for this gen too. So unless they want to make a Super-Duper Nintendo like in the 16-bit war days and compete again, they're going to lose gamers there.
All Nintendo has left is good game devs and some great IP.... and perhaps more trust with parents than the Apple kids-ingame-payments-debarcle has done to Apple's platform.