Shared library has some limitations though. 

Even a Polaris 11 to hit the performance marks that people are drooling about still has to run at 50 watts (that doesn't factor in the CPU either) and has to be clocked at an insanely high clock speed. 

That's still way above a Wii U even in power consumption (33 watts), which itself still would melt any portable form factor after about 5 minutes of play. 

To have that line up with a portable Nintendo handheld would be quite difficult. 

More likley what Nintendo is using are mobile chips for both. It would make a unified library much easier, which is why the Nvidia Tegra makes much more sense as it would scale much more easily into a handheld form factor. 

I think Nintendo is fed up with having their best/most expensive to develop games like the new Zelda and Splatoon not be available to their largest audience (portable buyers) and that's kinda central to the NX. 

If Nintendo can hit 1 TFLOP that would be nice, even that might be quite difficult if they really want a really functional unified platform. Any one can say "unified platform" but that really does not work if the console is like 10x more powerful than the portable with the console having GDDR5 RAM and an Intel CPU like people want ... that's completely unrealistic for a passively cooled portable to be equivalent to. 

Nintendo would  get it at maybe half that price so its very affordable for a modern and power efficient chip.  The portable will come later, and Im guessing would need to be at least 4x  weaker than the home con for reasonable  scaling. if home con nX is 2.5 tf, then 600+ gflop for the portable.  1080p home console, 540p (quarter HD) portable.

Polaris 11 is still way too hot for a portable passively cooled form factor even if you sliced the performance down to 1/4 ... it would still run at like 12 watts for the GPU alone, which means a portable would have to run at 14-15 watts factoring in the screen, WiFi, and CPU also. 

The battery would have to be the size of a lap top battery (Macbook Retina 15 inch sized I'm talking) to run that for even 3 hours.

More likely Nintendo is using mobile chips here, that means Nvidia or PowerVR or Qualcomm (Snapdragon). AMD just doesn't have the experience with mobile chips.  

I don't believe Nintendo would ever tie them like that to a western company. At least Sony is japanese, comes from a similar corporate culture and has gaming as a central part.

I do not mind the power input. I only mind the amount of content on the console itself. More third party support would be nice though.

And yet, both Sony and Microsoft are pretty much doing both.

This is what Nintendo needs to understand. We get it you don't care but devs do and it's affecting the amount of software on your system which affects your overall sales.

I think if Nintendo's goal is to have their games work across various hw, they will get it done.  For starters, using the same cpu architecture like ARM will greatly help.

 I mentioned "portable" but I suspect that if the first iteration of NX is the home console, the next would be a mini tablet (7 in) sold w/pro controller or attachable control dock.  I think the old school, tiger electronics HH format could very well be ditched or possibly a later NX product.  We saw with Wii U nintendo making a faux tablet ,so they are in tune with what is popular, but they will modernize this time (multitouch screen etc).  I believe with miitomo and future apps, nintendo will want to go with familiar HW design and that means tablet and phone format.  

As for power consumption, I could see that polaris 11 cut down and downclocked a bit, taking into the 40s watt range and still outperforming ps4. And tegra could very well power the tablet's gpu, but again, as long as both are using arm cpus it will make their work a lot easier.  

What about the fans who want cheap hardware over expensive and the developers who want a big install base to sell their games on? Do you care about them too?

The ones who can't produce good hardware are Sony and Microsoft. PS1 and PS2 had big failure rates, and don't get me started on RROD.