chuckd on 08 September 2007
http://www.gunslot.com/blog/top-twenty-five-25-best-selling-video-games-all-time
Nintendo = 17
Sony = 3
EA = 2
Rockstar = 2
Blizzard = 2
Square Enix = 1
Microsoft = 1
And yes, there's more than 25 there due to some number rounding.
For extra credit, try to guess number one before clicking the link. 2 hints. 1: It's a Nintendo game. 2: It's for the Game Boy.
