Given some of the hype they come out with about the game and the IP it was a given they were going to get a heap of people to give it a shot, same with Age of Conan, it sold a heap of copies initially.
Once you lose the player base it's a real uphill battle to retain them, if Age of Conan released in it's current state it would be a different story for them, would have kept a lot more people initially.
It would have been almost impossible for them to release Age of Conan in it's current form. The current form was fashioned after massive amounts of customer feedback. Developing a MMO in the dark for 6 years isn't going to make it better than a released game that takes a couple years to mature. The issue is that you can't charge 60 bucks for a half finished game and 15 bucks a month after that. You also have to contend with impossible gamer's expectations considering they've been expecting WoW2.0 and nothing else will do.
MMOs are a killer market. That's probably why it cost Bioware 300 million to get their MMO out.
Maybe they should stop developing them in the dark for so long?
What would it be like if they had a completely open beta from the point that there was a playable client and gave long term testers access to end-game prestige content on official Day-1, or a free year of game time, or something else?
It's true, but you can't really sell a game on the premise it will be eventually good, so yeah they are a killer market, well at least since WOW redefined what you had to do to have a successful MMO.
This is basically what Minecraft is doing - the game is entertaining now, but it's also got INSANE potential. So it's absolutely worth plopping $13 down on. Notch made $3 million or whatever (enough to fund game development) on the alpha sales. Of course, he may have trouble making money post-release if he can't charge the people who bought Alpha for the full version and if most of his potential audience buy Alpha or Beta.
Torchlight had the right idea, I think - create a fun initial product, and use the income from that to fund your more expensive V 2.0 that has a subscription model.
Once you lose the player base it's a real uphill battle to retain them, if Age of Conan released in it's current state it would be a different story for them, would have kept a lot more people initially.