The way to make money in MMO business is to be Blizzard and have World of Warcraft. Almost any other company (that includes the crazy huge and rich guys at Bethesda and EA/Bioware) didn't make a lot with their investment. Most of them haven't even made their money back. MMOs are a dead genre in this day and age for the cost they have of running them successfully. Sure, if you completely align your company and you have some angel investors you can build a production system that will churn out content with a very small team etc.. but big bucks? "The money"... nope you won't make "the money" with an MMO anytime soon again.
Even the classics we all love so dearly were never the big money makers. Sure their companies were successful, due to a stable subscription crowd, that didn't have anywhere else to go, but they are far from rich, hence them being sold time and again between different companies.