Kotaku had an interesting article about how user-created content has started to supplant studio-created content. The gist is that creating content by artists and developers takes waaaay too long... and studios are starting to come up with creative ways to get around the issue. Procedurally generated content is one solution - but another approach is to make content generation part of the game.
Second Life is the gold standard of this approach. It's not a game per se - it's a world where users can create whatever they want and make their world whatever they wish. The Sims did this somewhat, although the content is largely generated from the mod community rather than making it an in-game mechanic.
Spore is supposed to really take advantage of both user-generated and procedurally generated content. By creating your own... whatevers... that evolve into something on micro and macro scales.
Now that Linden Lab has released an alpha build of their Linux client long at last... it looks like I'm going to have to check out this trend first hand.
There goes the last of my productivity...