(Business 2.0) – Massively multiplayer videogames may never be as big here as they are in South Korea, where 40 percent of the population dukes it out in virtual worlds. But this fall, Seoul's NCSoft is spending about $20 million on two major launches, Auto Assault and City of Villains, in an attempt to win America's hearts and mice. Previous U.S. attempts--notably EA's Sims Online--haven't taken off, but the outlook is getting brighter: Blizzard Entertainment's World of Warcraft debuted in November and already has 2 million users.