microsoft

just cause i don't really like the american cut-throat business model(this has nothing to do with US but the profit hungry comporations)

Microsoft.

Let's see.

I'd never want Nintendo to leave, because they are the last classic console company left.

If MS left, they would probably make their games for PC instead of console, and a PC Halo would be too awesome for words. And a revitalized Age of Empires series would also be welcome.

If Sony left, Nintendo would probably get Final Fantasy back, and get most of Sony's japanese support. And it would be like an all-out western vs japanese console war.

Either way, two of my favourite gaming platforms win. Even though PC is where I do most my gaming, I think I'll still go with Sony though, because I'm a bitter Sega/Nintendo fan, and a japanese vs western console war would be awesome. And there is always the chance that MS would close down all thier studios altogether if they left.