I think Mario, Mario Kart, Smash, and Zelda would see an uptick in sales if they were multiplat, but I'm not so sure about their other IP.
I've said it before but I think Nintendo now has a stronger position, if Nintendo wants to do something like this, I think they'd rather pick one of the two (Sony or MS) to ally with and the price for that support would be steep.
I'd ask for a lot. 30% of third party licensing fees, ability to make their own Nintendo branded XBox or Playstation model, free advertising, input into all future hardware designs, and other perks ... and then I'd sit back and watch the two of them try to outbid each other.
IMO Microsoft would bite on that deal right now no questions asked, so you offer it to Sony as well and pit the two of them together and you got a bidding war on your hands.
But not before seeing how the NX goes.
I'd also consider an alliance with Google or Apple (do Sony or MS want any piece of competing against those two?) ... likely those two now see Nintendo in a new light. Nintendo has a lot of options now, they don't need to grovel at anyone's feet like Sega did.
