sega...oh wait...im late on that one :p
imo it would have to be sony, they have been an icon since ps1. yeah sure nintendo kept gaming alive in the most troubling times. but if it wasnt for sony i dont think nintendo would have taken gaming to disks for awhile, and then we wouldnt have any of the long awesome games we have now.
but then again...say if microsoft dropped out everyone would go crazy and be all like wtf?! and lose faith in consoles then that would be devasting...well i guess that can be said for anyone so scratch out microsoft and put *insert gaming console/pc giant here*







