I play Guild Wars -- even bought the Collector's Edition in Singapore (Thanks to Jerry for pointing out how ridiculously overpriced it is in the Philippines.) -- so I'm glad to hear it's hit the one million sales mark in a mere five months.
Guild Wars keeps server costs low by cleverly instantiating portions of the gameworld whenever possible -- thereby leveraging P2P connections between players -- while keeping community portions persistent. Other MMORPG developers would do well to study this model. Kudos to NCsoft for providing high-quality gaming without server fees.
Perhaps gamevertising and virtual economies will someday make all gaming free. Then again, if the whole 'Net takes on the gaming metaphor David Wong predicts, all gaming would have to be free.