I think really what's going to happen is Nintendo is going to make one system-on-chip design.

This for example will have an ARM core (CPU) + Qualcomm GPU. It will be extremely small and low on power consumption (3-4 watt usage). The chip will be able to generate lets say 275 GFLOPS of processing power.

Nintendo will put one of those into their handheld ... should be enough to run games at even Wii U fidelity at a lowered resolution (960x540 say) at 30 frames per second.

The "console" will be the exact same chip, just like three of them thrown into the box together (275 GFLOPS x3). With maybe 2x the RAM. That's still very low power consumption ... maybe 12 watts total, that blows away even the Wii U. They'll be able to put that into a casing slightly bigger than an AppleTV.

That should be enough to run Wii U fidelity at 1080P + 60 fps with perhaps even a few spiffier effects and/or high AA.

It could be super cheap too ... $149.99 or something after a year, might entice a lot of people to buy one on a whim just to play Nintendo games, and then it's served its purpose as far as getting people into the ecosystem.

Nintendo could make other variants too like a larger full tablet sized model (9 inch display) as well.

Based on new, classified info, it doesn't appear Nintendo is pursuing another console.