A recent Zoomin Games interview with Shigeru Miyamoto mentioned in passing that, in addition to Luigi's Mansion 2 for 3DS and Pikmin 3 to Wii U, he is also working on what ZoomIn called an "undisclosed original title." Speaking about that mysterious new project, Miyamoto said "If you ask me, 'Is it too much pressure to try to come out with something new?' I have to say no, I'm enjoying myself."
By way of explaining his own style, he gave us some idea of what to expect. "Each creator has his or her own field for which he or she is particularly good at," Miyamoto said. "I'm not saying that I am particularly bad at making the very photo-realistic video games. But when it comes to the realistic games, you have to create something familiar. I personally want to make something really different."
The rest of the interview is devoted to damage control from that time he didn't even actually say he was retiring from Nintendo.