Richard Bartle has published a paper on The Decline of MMOs. You should read it. It is not that I agree with everything he says, or the way he says it (all but one of the citations in his paper are to himself, what a narcissist), but this is one of those must-read documents if you want to up to date on the theory of games and gaming. Many points in the analysis of how we got to where we are now are spot on. The solutions he proposes not so much: For example making lots of servers with 250 players each has obvious problems a few months down the road when server populations vary widely and the game company needs to merge servers every month. Still, the paper is well worth reading and many of the ideas are worth considering. Recommended!