"If you're not running in [a limited] sandbox, how do you guarantee security?" Satchell told Eurogamer. "That's really where we've got stuck--making sure that nothing will hurt the user's system...it seems like some other platforms don't seem to care quite as much."

Microsoft's XNA programming platform currently allows enthusiast-level developers to create custom Xbox 360 and Windows games using managed code and Microsoft Visual Studio, though it restricts access to much of the higher-level functionality of the console. Beginning later this year, XNA users will be able to distribute their efforts via Xbox Live.

"I think [the democratized XNA] pipeline really is an incredible piece of innovation that will definitely enable other scenarios, and what's important about it is it's really addressing some of the problems with user-generated content," Satchell said.

While Microsoft is against any sort of unsecured game-modifying content appearing on Xbox Live, Sony has no such restrictions. The PlayStation 3 version of Epic's Unreal Tournament III allows user-created mods. The fate of mods in the eventual Xbox 360 edition is still unclear, though Epic has suggested it may end up being forced to have Microsoft certify some mods.

"I'm a little disturbed when I think about other systems and people using what we call native code—code that goes right down to the metal—and then allowing people to run script mods on top of that without the right security measures," noted Satchell. "It could be really dangerous."