According to a report at GamesIndustry.biz, ArenaNet has sold 3.8 million copies of Guild Wars 2 in China, surpassing the total sales for the rest of the world. Guild Wars 2 has amassed these sales in just over two months since the game's release in China.
The success of Guild Wars 2 is a vindication on two fronts. First, it is a compelling example of a game finding a significant audience with a pay-to-play model in a country where the market is dominated by free-to-play. Second, it is further evidence that the Chinese market is a lucrative untapped resource for developers in North America, Europe and elsewhere.
UPDATE: Shortly after these reports from 17173 started coming in, ArenaNet took to Twitter to announce that these numbers are not official, and that assumptions could have been made. See Twitter for details. Apologies!