Shigeru Miyamoto is still the man he is pretty much the key figure in creating all of Nintendo's big franchises and one of the key figures in making video games a global phenomenon.

All other answers are WROOOOOOOOOOOOOOOOOOOOOOONG

Tim Sweeney, all others are chumps.

Legend forever

He is decent even though I think the MGS series is very overrated (not as much as Fable, Mass Effect, Gears of War, God of War and Halo) but seriously can't put him ahead of Shigeru Miyamoto, Keiji Inafune, Hinobu Sakaguchi, Kazunori Yamauchi, Yu Suki, Koji Igarashi and Leslie Benzies I enjoyed their games a lot better.  I don't know who the key person behind the Uncharted and Assasins Creed frachise is whoever that is I would rank them ahead of Hideo Kojima also.

Ted Price, David Jaffe, Tetsuya Nomura, Hideo Kojima.  Any of those, really.

edit: Oh and Miyamoto.  I can't help but like him!

If we include former workers I would say Chris Seavor, without a doubt.

VIVA LA KUTARAGI-LUTION!!!!!!!

Kaz Hirai did an amazing job with the PS3, and I believe despite how the Vita looks now, it'll become a great success for Sony as will the PS4. He saved Playstation.

And Gabe Newell for Steam and for leading the most consistent game studio around. And for just being a generally cool guy.