Barring any crazy steampunk Retro-Zelda, the two clear options to me are Prime 4 or DKCR2. Honestly, I'd be happy with either (and it's possible that they could be making both). The Prime mechanics have some real possibilities with the Gamepad. Moreso than 2D Metroid, I'm sorry to say (but not TOO sorry, since I want to see that on 3DS with parallax scrolling). And I'm sure DKCR2 would be a super-solid game, especially if they took out the few annoying features of DKCR (you know which ones).
Honestly though I would expect a FPS. All the pieces seem to be in place. Nintendo wants back some of this core market, maybe the biggest genre for that market is FPS, and Nintendo has exactly one western studio who has made critically acclaimed first person games.
If I was to venture as to the type of FPS I think it will be something that:
Kind of obvious. Multiplayer is how shooters reach huge sales and become platform defining like they do. See: Goldeneye/PD for N64, Halo for Xbox, CoD for all platforms today.
*It will focus on gameplay above set-pieces/realism
I'd imagine it would be more sandbox in nature like Halo where the weapons are all distinct and are not just permutations of one of 6 classes. Retro has a leg up on competitors here by having experience developing Metroid power-ups.
*People will be able to use the abilities to approach the game in novel ways. Character builds in multiplayer.
*Totally new IP
Metroid's great but signing on to that franchise is probably a good way to assure your game will not set the sales charts on fire. Besides, if it is an FPS with a big multiplayer component Metroid wouldn't be the best pairing anyway.
*Shadowlink gets totally thrashed when he tries to take Stephen on in the much fabled DA vs. Wiimote throwdown.
The thing is I think Retro is working on something similar to Zelda, I think Nintendo (and any other company) is going to do that which they always do and slap the Zelda stamp on it. I really doubt they are working on an FPS. I know they probably started their project before we knew CoD was coming to Wii U but I don't think Nintendo would commission such a project out of their internal studio, especially with people that I would imagine don't have much experience with online games which is the big draw of such games. I think they are working on a WRPG or similar adventure title.
What I heard was that it is a new IP. Now, that could have changed since then (this was earlier in the year) ala Dinosaur Planet -> Starfox Adventures, but apparently it's a western focused game not based on an existing Nintendo IP. Here's what was said (roughly).
the game is for the "broader" demographic than the typical Nintendo audience. It is not Donkey Kong, Legend of Zelda, nor Metroid Prime.
I hope they are doing something in the action-adventure genre... they are so good at it. I don't really want Metroid Prime 4, though. Three of those games is enough.
I'm hoping that they have the resources to work on two simultaneous games, really, because I still want Donkey Kong Country 3DS as well... even if it is just B Squad recycling a lot of assets from the Wii game, or even another development studio being supervised by Retro and Nintendo.
@VickiL Whoa, I would seriously seriously seriously love if it there was a new Turok game (well technically there was on 360 I think, but it was nothing like the old games, and it sucked) in the style of the N64 classics. DAMN I loved those games. Crazy-ass weapons, dinosaur's with lasers strapped to their heads, super thick fog everywhere, what's not to love?