Iwata made Yamauchi the richest man in Japan for a short period.
I would actually say that Iwata is better than Miyamoto. Yeah, Miyamoto is a great at creating games, but being an experienced and intelligent game developer in the CEO position with a knowledge of business, Iwata can take Nintendo much further than Miyamoto could.
A game I'm developing with some friends:
www.xnagg.com/zombieasteroids/publish.htm
It is largely a technical exercise but feedback is appreciated.