Nintendo is grooming the talent internally but I haven't seen anyone of Miyamoto caliber in any of the Iwata Asks. That being said, the Zelda and Mario games are already in very good hands other than Miyamoto for multiple console generations at this point.
If Nintendo really wants another golden age of new IPs, then they are going to have to look outside because everything within Nintendo is tainted by Miyamoto's imprint and influence.
IMHO, Nintendo should go after top talent out of Ubisoft such as Michel Ancel or perhaps reacquire some lost talent like Dylan Cuthbert and others that went out and had a chance to evolve independently for a while.
I would hate for anything to disrupt the great things happening at Naughty Dog, Valve, Irrational Games, or a handful of other such development studios, but Nintendo would benefit to take some key talent out of those places as well.
