Quake 4 1.3 Point Patch will have a new multiplayer gameplay mode called Deadzone along with many new maps. The previews have also come up on the Quake 4 fan sites.
Here is what Planet Quake 4 had to say:
Instead of including an adaptation of a previously known game type such as CTF, Quake 4 1.3 includes an original gametype named Deadzone. The Deadzone gametype isn’t a mod such as Quake III Arena’s mission pack “Team Arena” was, but rather an additional gametype built into Quake4’s executable. Ten maps include this gametype as an option, three of which are adaptations of already included CTF and DM maps. Level designers will have no problems adapting their maps to include the features needed to play a Deadzone game.