But perhaps the game that really allows player and developer to work together in the most productive way hasn't yet been properly conceived. The first inklings of how this might work have come not from an MMOG, but from Will Wright, the creator of The Sims. His GDC speech "The Future of Content" argued that developers simply have to let players create, both thanks to spiraling development costs and from the sense of satisfaction derived by the players themselves. His solution was Spore, the apogee of the God-game concept finished off with a neat idea: mediated player-made content. Wright wants his players to be able to create new and unique objects for the game that can shared and downloaded from the internet, but without the undesirable messiness of Second Life. His game provides an easy-to-use editor that allows players to build diverse creatures from a set of adaptable prefabricated parts. Minor adjustments in the editor are dealt with procedurally by the game, so that weird new buildings and animals can be made to "fit" within the game shell. Because Spore provides definite limitations within the game space, while at the same time offering multiple variables to play with, players can't break the game or introduce anything incongruous. They can, however, play endlessly as they build. It's akin to Lego - there are multiple toys you can build with any one set of bricks.
This, then, is where I see MMOGs going: deciding on what set of bricks you want to play with, or, if you're a developer, deciding what set of bricks you want to provide. Games must find better ways to enable the player to build within the game world. This will partly come from the likes of, say, City of Heroes' character editor, which allows players to simply dress up in ever more imaginative ways. Or it will come from Guild Wars' concept of "instancing," but with players building, hosting and populating their own dungeons, into which unwitting strangers may wander. But it will also come from player's interactions with each other - using social and "economic" investment in a game to create content, as Eve does with its alliances and player-run businesses.
The challenge for developers is not to build the most beautiful game world, but to allow players to feel that they, themselves, are investing in something beautiful and with more depth just than killing enough blue goblins to get that brand new level-35 Stetson. Sure, the casual hat-coveting gamer will need to be catered to as well, but why not let the more dedicated players create that hat for him? Why not allow the player to set the quest himself, because he actually needs five hundred goblin toes?
Perhaps, if game engines ever manage to be truly approachable, then players will be able to customize almost everything about their worlds. A democratic, mediated customization - a little like how we live in the real world.
The wikification of games, anyone?