I dunno why people say MMOs are a dying breed. You can't account WoW's success as part of an MMO market. There was never an explosion of successful MMOs because, for some reason, WoW didn't add to the MMO market. It just created a WoW market for some reason.

Those 100 million accounts WoW has didn't go off to play other, more personally suitable games. The just quit the genre entirely.