Wright said he had learned the power of the phenomenon by watching players in his "Sim City" and "Sims" games spend hours customizing their characters and creating in-game objects that were traded online. His new game "Spore," still under development at Electronic Arts, is built wholly around this phenomenon. Players will control a species at it evolves from single-cell organism all the way to interstellar space-traveling "Galactic God," creating the look and personality of the species and, later on, the tools, cities, and even planets they used and inhabited.
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Allard told a story of meeting a 12- or 13-year-old inner-city child last year and introducing him to a basketball game on the new Xbox 360. Instead of spending hours dunking or trash-talking with his friends, the boy spent two hours creating a pair of sneakers, saying that was what he wanted to do when he grew up.

Allard referred to the idea as "the open-source model...for gaming," which is obviously a bit misleading since the interactions he's talking about deal with a lesser degree of creative input than, say, modding. However, I find it interesting that Allard and Wright (who tends to be quite vocal about his game design views) bring it up as something of a rising phenomenon in games. Allard seems to want to encourage the trend in general, and the CNet article refers to the potential for lowering asset development costs.

I always associated player-driven content in games as something more of an early-90s trait, with Sim City, Populous, and the like. If nothing else, I played a lot more of those games then than I do now. These days, "sandbox" design tends to be more exploration-driven (ie, GTA) than creation-driven. It's also a bit harder to reconcile Allard's view of the situation with Wright's, as the example Allard gives amounts to polish whereas the game Wright is working on unfolds entirely from player-created content. That said, they do occupy two ends of the same spectrum.

Oh, and I have to make a gratuitous mention of Allard's closing quote. Remember when Microsoft's Peter Moore explained that the reason the Xbox 360 has the "360" suffix is because it's "a living entertainment experience powered by human energy"? Well, maybe Microsoft really is doing some kind of Soylent Xbox thing. Just check out what Allard says here (emphasis mine):

"If only 1 percent of our audience that plays Halo helped construct the world around Halo, it would be more human beings than work at Microsoft corporation. That's how much human energy we could harness in this medium."