Imo it could work just fine. Since Nintendo can't rely on 3rd party support anyway, they could just ingnore them and develop a cheap handled device (I'd say an 199$ console), that can be connected to the TV and display WiiU-like graphics at 720p, controlled remotely  with wimmotes and pro controllers. (by 2018 maybe it could be possible). It would be powerfull enough for an handled system, underpowered for an home console (but since when this was a problem for the Wii at all?).

Since they would only need to concentrate all their resorces on a single platfoms they could deliver a larger first party library, without dorughts. Yes this would mean less hardware incomes but also less marketing costs, less costs to make tools and to train developers. From the customer perspective, for a N-gamaer this could mean less money spent on hardware, which means more disposable income to buy N-games, for a non N-gamer a single console to gain access to all Nintendo games, whitout droughts + an handled console to pair up with a Ps4/Xbox3 would look more appealing than current Nintendo consoles (imo), for parents who whant to buy a console for their kids it's just the next cheap machine to play Mario and Pokemon.

No is not feasable at all, the energy consumption would be too high, and that thing would suffer from extreme overheating.

You could be right, but it's a bit early to tell, isn't it? Look at Golden Abyss on PsVita, it doesn't look much different from a ps3 launch game, of course I'm not going to argue the PsVita is like the ps3, but it is also one year old console. In 5 years from now mobile processors are definetly going to be more powerfull.

It would probably dominate Japan and streamline Nintendo's business as they would only have one platform to support and advertise. It ultimately will depend on HOW it manages to be both a handheld and home device that will determine its success.

I completely agree.

Hopefully that day will never come, although with the current Nintendo I'm always prepared for the worst possible scenario.

I do think its a good idea, but the format has to be studied.

I think it must be a portable wich can connect to the TV and be a console aswell (the key feature beeing that it must look like a portable system, wich is a market Nintendo cant risk losing). But, this might be harder than it seems to pull off because first it must match next gen technology, it must be priced reasonably and must use a media storage that is capable.
This device having the full undivided atention of Nintendo development would no doubt become a more atractive proposition than the 3DS and the Wii U are separatly.

I don't want to see it. I don't think we will see it. I think the only way we would is if the market really changes due to tablets and smartphones, and if WiiU totally bombs. I think what we will see is a very connected WU2 and 4DS.

That idea involves a lot of risks and opportunities. I for one would be happy, if the WiiU would play 3DS-games. Think of it: play mobile your game, and as you're at home you put the cartridge into the WiiU, play on the big screen and gamepad with the same save. Somewhat like Monster Hunter, only that MH3U needs you to buy two games (for 3DS and WiiU) to do this and has an extra step synchronizing the save-data.

My improbable nerd dream would be a Nintendo phone/handheld that runs on Android, with seamless integration to the television as a console. The integration would be something like Apple TV, but better.

You'd carry around all of your user data on your phone. If you visited someone else's house with their Nintendo home console, you could sync your phone with bluetooth to the console and play with your data.

This is.. of course, pretty improbable. I don't even know what a Nintendo phone/handheld would look like. I would just like this because I love reducing the number of devices I have. And I value the heck out of my SIII, so in my ideal world, Nintendo would create something better than my SIII.

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