I also had the idea that he was doing a FPS, when people talked about his new IP, but after Iwata said they were working on some NFC games, I kinda lose hope for it, Miyamoto can easily connect with the kids and casuals, so he would be the best choice to do a NFC game(along the people at Game Freak, doing a Pokemon game), so unless the NFC game is a FPS, I doubt Miyamoto really is working on a FPS game.
COMG guide to points: 1 point = Raging. 2 points = Beasting. 3 points = Tearing it up. 4 points = Berzerk. 7 points = Rampage. 12 points = Burst. 15 points = god mode. 20+ points = DIVIDING BY ZERO!!! 40+ points = Youkai (originally Pokemon).
-1 = Negabeasting. -5= NegaRampage. -10 = NegaBurst