Possibly another console flop and Zelda will appear on PS4. I can dream, right?

My shot in the dark - It's a new handheld that can also be played on your TV via wireless HDMI connector, like Chromecast.

The end of the world? o:

I hope it's a fusion device. Out of all the options, I feel like this one has the potential to sell and make the most money.

A Pet Frog

It will be a boat/airplane console, so conquering an up until now unexplored market, and giving Ninty a monopoly on it tht will last undisputed for at least four year, worst case if competitors will react as quickly as possible to put their competing device on the market.
It will use three or four additional sensors, made each with 3 gyroscopes and 3 accelerometers, to be bolted or riveted on the deck in a triangle or square shape to provide info on the vehicle motion to be subtracted from the motion control interfaces info vectors.
Later Ninty will be able to grab another monopoly adding sensors to detect gravity or its absence and making the spaceship console.

It's the next Nintendo system.

NX is a home console that brings some sort of new Nintendo witchcraft to the table. "N" being the home console. The home console will also connect with current hardware in some way.
Once the home console is out on the market, Nintendo will announce "X".. "X" could potentially be their new handheld. This handheld connects with the console naturally, adding new ways to play. Additionally, the handheld will bring features to home console games in some form of street pass.

This theory makes a lot of sense to me.. Nintendo tends to experiment in the market before going all out with their full vision. This also explains why they might be so easy on their budget with the Wii U, and we haven't seen a price cut yet.

"N" being a console with a traditional controller not only makes it less expensive, but brings more appeal to lazy devs.(I kid about lazy.. kinda). "X" being   separate from the console gives players the option of not having to use two screens if it doesn't appeal to them. This plan could allow Nintendo to do what they want, while also providing said options to those who aren't very much into their craziness.

NX doesn't need to be more powerful.. it needs to be open minded and welcoming. Nintendo are already much different than the other two. That will always be their selling point. The only need something far more welcoming and common to the market to let others in. Once they're in.. you teach them how different you are in an inviting manner, rather than having them feel forced.

It's Nintendo's PSP Go.

I thought it was a handheld at first, but now I'm thinking more of a home console