This was confirmed in an interview with Forbes in which Miyamoto was quoted as saying, “I’ve pulled myself back out of some of the hardware section and I’m really focused on some of the software I’m involved in–for example, the new Starfox game. Of course, I am observing and looking at the hardware, but I am not actively participating and making decisions.”
We suppose for some gamers they might be disappointed that he will not be involved. After all being involved would also mean that he could be responsible for having input in the hardware which in turn affects the kind of games he could later create, but it seems that Nintendo believes that Miyamoto’s efforts would be better off in trying to get more gamers on board with newer games.
In the meantime Nintendo has not revealed any details about the console just yet, but they are expected to come 2016. However last we heard, the console was reportedly pitched to third-parties in secret at E3 2015 in which the initial reactions to it were largely positive, so here’s hoping Nintendo will be able to surprise us all.