World War II Online is considered by many to be the first MMOFPS, though it is also a massively multi-player simulation or virtual battlefield. It was released on June 6, 2001. The launch of World War II Online is a legend in the game industry and it has managed a steady pace of updates.
Would you be upset if I went into Wikipedia, edited it to say it's the biggest MMO bust of all time, and used it as a source? Because you know, even Charles Manson can edit wikipedia.