I'd still buy it, but I don't see NX being a handheld.

Erm... Cutting their own generation in half basically showing the middle finger to the only people that still care for them, their fanbase. Then releasing new hardware in mid cycle during an extremely successful ps4 which will be probably receiving its first price cut and all the big hitter titles that will obviously make and even starker contrast to a out of nowhere home console carrying the bad taste of the wii u. Then either the console is merely on par with the ps4, in which case it will be criticized for being too weak. More powerful than the ps4 which would make it very very expensive and at best get the same 3rd party games the ps4 will get, which will make people wonder, why pay more when a cheaper and more established console plays the same games in a much bigger userbase.

3rd option they go for cheaper hardware still less powerful than the ps4, in which case everyone will ask, why not just stick with the wii u and give it a normal controller.

Enough reasons? I could go on

It's not.

Nintendo consoles usually have lifespan of around 5 years, if NX will release next year, it would be 4 year of Wii U, just one year less than usual Nintendo console and thats not big deal, we saw something similar with original Xbox, and we all know for Xbox 360 success.

Nintendo probably will not compete directly with PS4/Xbox One, they are probably doing again something similar like Wii, affordable console (cheaper than PS4/XboxOne, probably around $250) with new concept of playing (maybe hybrid device).

I'd prefer if it was but I don't think so. Given the lack of future game announcements for the Wii U, they clearly want to replace it soon.

They are not competing with the x1 and ps4? So they are competing with who then? Ford and Audi? Coke and Pepsi? Who are these mystical creatures that will buy a nintendo home console that don't by the time own a ps4 or x1? Why would any current nintendo fan buy again an underpowered console that would be decimated yet again just like their previous wii u? Hybrid device for 250$? Lol... The 3ds when it came out it costed 250$. You're imagining nintendo can afford to give you a home console and handheld for the price they sold their previous handheld for... Sure... Ok then...

An even better question, I think, is how many settings this toaster would have. 

A 2016 release would give Wii U 4 years, not 3. It's not likely trying to compete directly with PS4 so that consoles success would really have little to no bearing on how successful a Nintendo console would do. I agree with u on option 1 & 2, no need to make it as powerful or more powerful than PS4.

I think option 3 is what they will and should go for along with a unified platform where all or most games are compatible between the console and handheld. The reason why not to simply stick with Wii U is because it's expensive due to the outdated components and they can't support 2 distinct platforms at once, especially since the 3DS successor will take more time/resources than 3DS so how are they supposed to give adequate support to Wii U at the same time?

I say release a handheld and console with the same architecture, operating system, online infrastructure, account system, rewards program, that share a library that has allows for cross-buy/play/save. Have the console be a slight boost over Wii U, similar to the jump from GameCube to Wii, basically faster CPU and more RAM, with the handheld version being a device that can run the same games at a lower resolution.

Like I wrote, Wii didn't directly competing with PS3/Xbox 360, PS3 vs Xbox 360 competitions was very strong and head to head competition for hardcore gamers (there is reason why called them twins), Wii was targeting everyone from 5-99.

Why would Nintendo fan buy again underpowered console!? Because they love Nintendo games, most of Wii U owners are satisfied with Nintendo suport. And Nintendo clearly dont count only on big Nintendo fans, they next hardware will certainly be more attractive console than Wii U (Nintendo completely failed with Wii U in more different ways).

Yes, Hybrid device for around $250, why not!? 3DS $250 launch price does not indicate anything, you forgetting we had previous home console at same price.

Nintendo said they preparing hardware with new concept of playing and they indicate they want affordable price and that they not going for most powerful console on market.

Just because they are consoles does not mean they are direct competitors, Wii was not aimed at the same type of audience that PS3/360 were.

Ur right, a single 2-in-1 device will not likely be able to retail for $250 but they can have a separate handheld & console that share a library each for $200.