Tim Willits from id software is answering questions about the fourth incarnation of Quake, which has been under development since shortly after work started on Doom 3.
Here is what Willits says about sources of inspiration: "While there hasn't been one single title that has influenced development of Quake 4, the developers have played a number of other games, such as Halo, Halo 2, and the Call of Duty series. But these have been played more as fans than as particularly picking and choosing game elements to include in the game."
