There's basically just rumors and speculation.
Nico Wav, the guy who broke the Devil's Third rumor, says Nintendo has 3 other 'mature' titles similar to Bayonetta and Devils Third coming to Wii U.
Optimistically, we may *hear* something about Retro's new project, but that likely won't come til 2016.
And also the Diddy Kong Racing rumor.
And I have my hopes pinned on a Rogue Squadron remake/remaster. With the new Star Wars movie out in 2015, it makes sense for Nintendo to exercise whatever publishing rights they have to SW titles.
I predict NX launches in 2017 - not 2016