As the owner of a phone, tablet, laptop, and original Wii, Im not sure where I feel like this would fit in. Like Rob said, Im likely not their target demographic (clearly - im older than all the users they showed in their commercial 
). The games I play are time wasters while im in the waiting room at the dentist - its been some time since I put any real time into a campaign type game, and even that was on my android phone. The Wii was a fun idea that was actually fun, but was expensive (at that time)... and basically was used at my house to entertain: bowling and tennis and stuff for when the niece and nephew or friends came over and such.
Its kind of like the solution for a problem that I dont have...it looks cool, and the functionality seems there, just not applicable to my lifestyle.
That said, SWMBO received an original iPad as a gift from clients at work, about 2 months after it was released. At that time, I really didnt know what we were supposed to do with the thing. After about 20 minutes of web surfing, I would get bored, and go play in the garage. But, after about 2 or 3 months, we couldnt live without the thing.
We both have since evolved to where our phones are more powerful and more convenient (size/portability, battery etc), so we dont actually use a tablet much at all (we also have a 1 year old Kindle fire that is only really used to watch videos on the plane or on a road trip). But my point is that we eventually learned when to use the (tablet) solution that we didnt immediately realize we needed. Once upon a time, it was a novelty, but the concept of the tablet now has taken hold so firmly (in the tech world), its clearly not gong anywhere, and is even slowly replacing the laptop (new Surface?), even in data heavy business. Theres the possibility that a similar situation evolves with something like the Switch in gaming: an ultra portable, modular device could carve out a role, and end up replacing consoles.
What Nintendo really should have done was created a modular design that was compatible with a current large-screen phone - im thinking something like a Note or the new Google phone or the like. Heck, the new Moto-whatever is offering its modularity with camera and projector add-ons as its big selling feature. The phone base gives it touch capacity, so that it can fill in as a web or email device, and by adding the handles, it becomes a portable gaming device. Drop it onto a dock, and it instantly is available for a large screen.
I realize that by partnering with a specific line of phones, that it would limit the number of people that would be potential consumers. But it would also bring the cost down (well, bring down the cost of development, and hardware. I have no idea what licensing costs would be involved). Plus it would bring up issues when the phone model is updated by the manufacturer - ensuring reverse compatibility would be an issue. But, I have to think that there are work-arounds. I would bet theres room in the design process to build bluetooth or WiFi connectivity into the handles so that the phone model could essentially be unimportant altogether.
Consoles in the past were all about their processing power. Nowadays, you can potentially find more processing power in a cell phone (new Google phone sports a 2.5ghz quad core unit IIRC). An external battery would give it hours of gaming power to run that chip set. Many phones are offering 32 and even 64 gigs of on board storage (or more with expand-ability). Theres not much a console can offer anymore that a high end portable device cant meet, or beat in some cases. Its the nature of the tech beast - make it smaller, stronger, more useful, and the people will beat a path to your door. Gaming rigs are no different. Its just a smaller segment of the populace that is a potential consumer, so the industry is a little slow on the uptake.
EDIT:sorry, i never intended on that becoming a book, my mind just kept going. TLDR; I think its cool, but its probably overcomplicated. I will wait 2 years, and get them on Craigslist for $50 when college kids need to sell them for gas money.
. I'm old, so I can't read off my phone for more than 20 minutes or so. Laptop for use where ever I end up. I'll admit the tablet is doing more and more, but still can't do everything.
I have this one, but they also make a Zelda one. It only works in handheld mode (there's no battery for it and it gets power from the system) but it makes playing old-school games so much better. Well worth the $20.
