^that's pretty obvious, expecting him to helm the company about 5 years before retiring....
the next one most likely shinya takahashi if they want to do another dev -> boss

edit: looks like for now, he's only appointed for a year... probably will continue for another few years if the shareholders are quite happy with him and the next one hasn't been groom well enough yet
https://twitter.com/serkantoto/status/643446109973704704