OS News has an interesting article about the how good open source games are and why it doesn't make sense for game development. According to the author, "despite the impressive list of achievements of open source software, it can be argued that there have not been any world-class games created under the open source banner. Sure, several old games like Doom and Quake have been gifted to the open source community, but there are no comparable original creations in this area. One should not expect this situation to change anytime soon, because the open source development model does not make sense for game development."
The article can be read at OS News