During the recent shareholders meeting, Iwata said that Nintendo had several 3rd party partnerships developing unannounced titles.

Just for fun, I've made my educated guess at what these titles could actually be. These are purely guesses, but they are based on the kind of partners Nintendo has more recently favored to work with. I think Koei Tecmo, Namco Bandai, and Sega are the most likely business partners for such work.

Here are the kind of titles I figure are being worked on:

Fire Emblem vs Dead or Alive

After the success of Hyrule Warriors, a lot of fans have asked if Fire Emblem Warriors would be next. I for one don't think Nintendo will take the bait in creating another Warriors offshoot for every franchise they can. But I do believe Fire Emblem in particular is a series Nintendo wants aggressively use the IP of and position gamers who like mature titles.

I'd imagine Nintendo would definitely want to work with Koei Tecmo and Team Ninja again. Now that Hyrule Warriors has shored up Musou games as a whole, I think Koei Tecmo / Team Ninja has their eyes set on reviving another IP that lately has been stumbling: Dead or Alive. 

Since Fire Emblem has now increasingly taken a much more adult direction, and since Fire Emblem characters are arguably just as popular as fighters in Smash as in their own games, the DOA crossover actually makes sense.

The result would be a fast, violent, sexy, hardcore fighting game that's bound to make heads spin in the right way. It could undoubtedly introduce a really interesting story and umm... other mechanics... like dating and marriage, right? That's something DOA and FE fanatics really have a common interest in.

I think a Fire Emblem vs Soul Calibur game could just as well happen for the same reasons. However, I think Namco Bandai's resources around the WiiU will remain primarily focused on Pokken, Smash, Project Treasure, and another title called...

Ace Combat U

The lack flight combat games on WiiU is truly sad. The gyro controls and 2nd screen could be used to create something really special. But I don't think much of anyone has realized that yet.

However, once Starfox Zero drops, it'll clearly show that possibility to the masses. And I think then there will be a desire for more of these kind of games on WiiU.

So why this game? This IP? 

Namco Bandai made Starfox Assault, and undoubtedly tried to bid for the work on Starfox Zero.

Namco Bandai has seemed particularly eager about this IP on 3DS - which would lead me to think that the producers of this series may have a soft spot for the WiiU as well.

Based on this, I figure there's the right alignment of resources to get this to happen. In a way, Nintendo used Starfox as means to the end of finding out who would want to make a flight combat game on WiiU. 

House of the Dead

Another genre sorely lacking on WiiU is the rail-shooter genre. For rail-shooters, House of the Dead is the best that they come. Moreover, other than Resident Evil and CoD, House of the Dead was really the most successful M-rated game series on Wii.

 It's probably pretty easy for SEGA to develop, so the return on investment should be rather strong even if Nintendo didn't make an active effort for new House of the Dead game to be produced.

With Bayonetta, Devil's Third, and Fatal Frame all greenlit by Nintendo, it's pretty obvious they'd probably like to bring an established grindhouse horror style of game to the WiiU.

Overall, it's easy money for SEGA in an era which they need it pretty badly.

What would you think if Nintendo actually announced these very games? Do you think my guesses could be in any way accurate?

Probably more Amiibo stuff.

I wouldn't be surprised if Sonic Team had a title in development that made use of Amiibo.

A more extensive Sonic series of amiibo could sell really well and help breathe some new life into the franchise, if the game supported it right.

Nintendo vs Capcom
This is my one dream

I don't really think Dead or Alive x Fire Emblem would work very well, but I would indeed like to see more crossovers with the Fire Emblem series

Nintendo needs something massive. Little random bread crumbs like Bayonetta 2 won't do anything. Again, they should either buy Capcom or do a Capcom 5-level exclusive deal with them. Do the same thing with some western publisher. Profit.

lol, I was thinking the same.

How would Nintendo paying Capcom make them more dead. I guess SFV's exclusivity is killing Capcom too.

he thinks that getting Capcom games won't sell well hence both Ninten and Capcom would just lose $$$.

I think that's wrong, especially with the right games. No experimental titles.  Just games and established franchises. Monster Hunter, Devil May cry, resident evil, mega Man, and Nintendo versus Capcom. It's the lineup that would make it sell. The quantity in tandem with the quality. Even if not all of them were specific sequence, they would sell well. Devil May cry could be a crossover with Bayonetta. Resident evil could be a spinoff in the same vein as Revelations. As long as they remain exclusive, and they have adequate production values, they will sell.