I just don't see it happening. Nintendo is fundamentally different from almost every other hardware company out there for one reason: they only give a shit about video games.
The whole point of this argument is the idea of Nintendo producing a multi-purpose machine that the mass market would want to buy, and then play games on it. Sony and Microsoft can do that because they have experience in other businesses. Nintendo doesn't even give a shit about making their console able to play DVDs. They'll allow some media streaming apps on there, but that's it.
I could maybe, maybe, MAYBE see Nintendo one day trying out some kind of small tablet (standalone) with a lot of non-game software support. Functionally though it would be the same as the 3DS or any other Nintendo handheld, and those things are first and foremost designed to play Nintendo's games. The company wouldn't be willing to make a device with a lot of consideration for non-gaming use.
Ans on the hybrid argument, the most I'd see Nintendo doing is one day releasing a console and handheld that run the exact same OS and software, making every single game cross-buy. Their handheld and console games are getting more similar, but Nintendo still wants that dual revenue stream. Their console business would have to evaporate 100 percent before they gave up on that model.