As a keynote speaker at the Linux Foundation's 2013 North American Linuxcon, Newell explained that the old proprietary ways were no longer working for gaming companies. In no small part that's because the economics of games are changing. Newell said, "Games are becoming nodes in a linked economy where the majority of digital goods and services are user generated rather than created by companies."
In fact, Newell said that Team Fortress Community is already creating 10 times the content of Valve's Team Fortress developers. Newell has no doubt that in head-to-head competition Valve could take on any of the other gaming companies. But there's no way they can beat the content of their community and companies that don't realize that it's the gamers, and not the developers, who are calling the shots.