MS or Sony leaving would be bad for gamers.

Nintendo leaving, I think has the least impact. It would destroy the handheld market though.

MS, but not entirely. They need to get out of the console market, because they're just simply not good at it. They should stay in software and maybe offer their online services expertise to Nintendo.

You mean, "after playing Catherine on 360"*

Ideally I'd prefer for them all to stay in the game, but if Nintendo doesn't get their act together, then they can get out for all I care. At least I can see a future for M$, they're expanding their horizons. Nintendo has been stagnant for years. They have a rich history, but that's not reason enough for them to be allowed to stick around rehashing their old titles, leaching off of their most dedicated fans.

Microsoft.

Grrr.

King
http://en.wikipedia.org/wiki/King_(website)

Voted MS so they win a VGC poll!

Microsoft, they only really gave us online gaming done properly.The industry was already headed that way. They dont serve a purpose but to basically be a shadow on Sony's back. Their major IP's came from outside companies so really...what are they bringing to the table every gen? Very little.

If I had to choose one then Microsoft. But like others have said all three are essential because they each push each other to be competitive.