I glance around at the underbelly once in a while, and there's precious little in the way of Nintendo rumors, or any major rumors at all really. The PR machine of the major publishers has learned to wield forums to hype pre-press releases for standard products. Like, "RUMOR!!! Square-Enix to announce FFXIV release date soon!" And outside of that Smash ESRB blow-out, Nintendo is friggin' air tight.
The only thing I've read, which has been kicking around for months, is that Nintendo is supposedly working on an HD remaster for the WiiU to release in 2015, anything from an N64 to a Wii title. And that's vague enough to just be common sense/idle speculation.