Valve has announced that we are to be one of five mods chosen to be hosted on Steam itself. In short, this means that you can expect automatic updates straight from Steam, and Steamworks integration in subsequent releases! We look forward to better serving the community with a great release system, and to patching fixes and releasing content more quickly this way.
You can view the story here. A big thanks to the entire ZP team, to the servers who host us and keep us popular, and to the community for making this game fun in ways we could not.
Told you guys we'd have the next release soon.
-Zombie Panic Development Team