Really sad news. Iwata has to be one of the few video game CEOs I genuinely respect.
-Began his career with the intent of going into technology and video games (even against his father's wishes) as opposed to business.
-Had actual experience producing and programming games before becoming Nintendo's CEO.
-Made Earthbound just straight up work.
-Made Pokemon's battle system function on the N64 in Pokemon Stadium with no documents to help him whatsoever.
-Compressed the code of Pokemon Gold and Silver so that GameFreak could add the Kanto region.
-Debugged Super Smash Bros. Melee by himself so it could release on time for the launch of the GameCube.
-Seemed genuinely passionate about the work his employees did (See just about any Iwata Asks interview)
-Seemed genuinely passionate about video games himself (See all the games he has work on, his antics in the Nintendo Directs, and this quote from him... "When I first started making Kirby, there was a kindergarten right next door. I'll never forget how moved I was the first time I saw doodles there of Kirby. That may have been the first time I realized that the world would recognize what we had made. Because of that feeling, Kirby is special to me.").
-Willingly took a 50% cut out of his salary when the Wii U wasn't doing well so he could drop the Wii U's price and wouldn't have to fire anybody.
-Did what he set out to do by more or less making games that were fun for everybody.
I think it's safe to say he will be missed.
EDIT: Oh, apparently he also insisted on this intro
being included in Kirby's Adventure. I'm going to think of him every time I see that from now on.