The Future Of MMOGs - You As Designer?

Thanks to GameSpy for their feature discussing user-created content as the future of massively multiplayer games. In one section, Will Harvey of There Inc. discusses potential problems with more exotic player-created features: "If third-party developers [A.K.A., gamers playing the game] write games for an MMPG, will the code for those games also run on the servers? What if it crashes?" Elsewhere, Will Wright talks about quality issues after players create content: "Once we have the ability to leverage the creative process, how do we move that content between players in the most efficient way? There's always some content that a small number of players create that will have the most appeal."