Here are some details that have come out today:
* Weapons and the Arwing can be controlled independently.
* All-Range gameplay was in one of the demo levels, with Falco and Slippy as wingmen
* In a nod to Star Fox 2, the Arwing transforms into a tank. (Farewell, Landmaster, you served us well)
* One of the demo levels featured a Star Wolf battle
* The third level was the most-interesting:
* The main enemy was a Kaiju-like monster.
* Other enemies included quadroped robots
* Hovership with a remote robot
* Story seems like it will be very little.
* You will be able to choose levels to play
* Nintendo is seeking development partners for the game
* The game was not intended to be shown at E3, but Miyamoto "liked it enough" to show. TBH, I think they had to show it to generate hype for the Wii U.
* The plan is for an episodic release
All-in-all, it looks like this will be a VERY different Star Fox game. Using both the gamepad screen and the TV is pretty much required, making off-TV play highly unlikely.
The game is VERY VERY early, and the things I am ready are suggesting that it really was TOO early.
In a strange move, Nintendo released an asset dump for the game that is quite puzzling: The picture in the previous article, the Star Fox Assault logo without the "Assault," Star Fox 64's title screen, a screenshot from Corneria in SF64, and a very unprofessional screenshot from Corneria in SF1 that looks like it was taken with a cellphone camera.
Given this, I highly doubt this game will be ready next year. Despite Miyamoto's assurance that this will be a 2015 title, I think it is more realistic to think into 2016.