I agree with some of the posts above. There won't be another Nintendo console, not in the way you traditionally would expect.
They will make a handheld that will be about as powerful as the Wii U, and that will either connect to the TV, or have a cheaper "console" variant ... which is the same chips, maybe overclocked or featuring extra cores for TV play.
The handheld will render up to 720p (but most taxing games will run at 480-540p), whereas the TV variant will run the same games just at 1080p resolution. Wii U quality graphics (more or less).
It will be like the Apple set up ... there's iPhone, iPad, and iPod Touch that all share the same game ecosystem and similar chipset components, some have different screen resolutions but are otherwise basically the same thing. So it doesn't really matter if say iPod touch isn't selling so great, it's just an extra variant.
