According to this, EA has confirmed at GDC that The Sims is about to hit the 100 million sales milestone.
"The Sims is a highly successful entertainment brand," said EA's vice president for global brand development of The Sims label Steve Seabolt. "In fact, we're coming up next month on selling our 100 millionth unit of The Sims, so it's mega, mega... We make so much money from The Sims - it is so profitable - that unlike other businesses, we don't have to sell it out with advertising and sponsorship and flog the user with advertising to make money."
We're not 100 percent certain, but we're pretty sure that makes The Sims far and away the most popular videogame of all time, on any platform and on any genre. We can't for the life of us think of anything else that comes remotely close. Go Will. Bet you can't do it again with Spore.