Civ V: Cold War
With the significant changes to diplomacy and social policy system, maybe it's time we finally see some sort of Cold War gameplay. Civ V is not going to recycle the same expansion packs from Civ IV, and I don't believe they're going to introduce religion or espionage because, like they've said, they have new things they're introducing. I believe this is the new diplomacy and social policy system (formerly civics), so it's the perfect time to create a Cold War expansion pack. This is something that would get me really excited as well.