If true, that's suicide. Some people favour smartphone and tablet gaming because phones and tablets are mainly used for other things they care about, while games are just a little extra. A dedicated hardware that would aim to replicate that sort of experience is geared toward horrible failure: the people who don't care about gaming won't want it because they already have what they need, and the people who care about gaming won't want it because it lacks the experience/comfort they seek.
It even makes less sense if you consider this isn't even a handheld and you're supposed to look at the TV while you use this thing. And it even makes less sense after the failure of the Wii U: why base everything on a gimmick that was widely ignored or rejected and throw all the rest out of the window? It's so mind-bogglingly idiotic I believe 90% it's fake, even without considering the aberration of the weird cropped image on the first "leak".
It'd make a little more sense if there were attachments, but what would be the upside of putting all vital input on an attachment? At least the Wiimote made sense without the nunchuk since it allowed to play games NES style, and separating the two halves of a classic controller with the nunchuk was actually a neat idea. Here, there is no upside whatsoever to a hypothetical attachment, especially since you're supposed to watch the TV, here.
Even if you think it's true and Nintendo has thought this thing inside out and it turns out it actually works, on a marketing/media/image level, they'll get completely destroyed no matter what they say. The Wii and Wii U did work (and the Wii U actually mostly plays in a completely standard way), and yet Nintendo's image still degraded because of the sent message, and it'll be worse here in an exponential way. I loved the Wii and love the Wii U, the Wii U is my only current generation console, but if this thing is real (which I really doubt it is), I'm simply not interested and will just go on playing on Steam. It's an absurd design.