I'm expecting some more in the range of 3x more powerful than the Wii U.
I think Nintendo views that as plenty, and they will be able to get a mobile chip from PowerVR or AMD (+ ARM CPU) that they can use in both their handheld and home console/dock version.
As I mentioned in the other thread, the PowerVR GT9700 is apparently tailor made for mini-consoles, is cheap, and has monstrous 800 GFLOP performance for a mobile-family chip.
I think Nintendo would be very, very happy with that type of chip. It would probably only sip about 15 watts of electricity too ... less than half of the Wii U, which is something else Nintendo would probably like.
We're reaching a point anyway where graphics leaps are starting to level off. It's not like Mario Kart 8 or Zelda U look like crap even after putting several hours into Arkham PS4.
If they can get a mobile chip that gives them 400 GFLOPS in the handheld and 800 GFLOPS+ in the home version ... I think Nintendo will be very pleased with that, hell, they might not even use that much power themselves. Nintendo is not competing with Sony/MS, none of the Sony/MS fan base is really going to be impressed with a Nintendo system that's only matching/slightly exceeding the PS4 come 2017 anyway.
That's just a dead end. If they want to go that route, they must have a system at least in the 3 TFLOP range, which would be very expensive, and you can kiss the fusion idea of sharing a library with the handheld goodbye too, because a handheld at 500 GFLOPS max is not going to scale well with a 3 TFLOP big brother. Too big of a gap, it would be like (well) the Wii U trying to run PS4/X1 optimized games.
