Here's an appetizer:
Basically, GCM allows you to make changes to your country before you start playing. You can simply tweak a couple of techs if you like, but you can also pretty much start from a blank slate and re-design your country as you choose. Simulation's great and all, but we appreciate that sometimes, you just want to run a war. So we thought we'd help you by speeding up the early years for those gamers who would like to jump straight into the action. We hope that this will be an interesting option both in single and multi player, SP users can experiment with different setups, and MP users will be able to start later scenarios with their own custom setup without having to play through years of peace to build their desired armies.
If all goes according to plan, expect to find this expansion out on the battlefield this Fall.