How is GB not excited about this! Full on expansion Gods and Kings announced!
Tons of New Stuff. I know I just mentioned it, but I want to draw attention to just how many new things we've got here: 27 new units, 13 new buildings, 9 new wonders, and 9 new playable civilizations. Among the new civilizations are the Netherlands (William I, Prince of Orange), the Celts (Boudicca), and the Mayans (Pacal the Great).
Religion. That's right; quite possibly the most requested major addition to the game is coming in the Gods & Kings expansion. Using the new "Faith" resource, you'll be able to found your own religion and grow it from a simple Pantheon of the Gods to a world-spanning fully-customized religion.
Reworked Combat System. The expansion has a reworked combat system along with an AI that places more emphasis on balanced army composition. Among the changes to the combat system is the addition of melee naval units, which will force you to really rethink the way you execute your naval assaults.
Enhanced Diplomacy, with Espionage. In addition to being able to establish embassies with your rival civilizations, spies will now be an important part of how you conduct your foreign affairs. Surveilling foreign cities, stealing advanced techs, and garnering influence with city-states are some of the things you'll be able to do with this new powerful mechanic.
New City-States. With religion being added to the game, it only made sense to introduce Religious city-states which will interact with your religion in special ways. In addition, Mercantile city-states will be attractive for those of you who love to grow your civilization's treasury. All city-states will use the greatly expanded quest system, making city-states more dynamic and diplomatic victories more challenging, while decreasing the importance of gold when dealing with city-states.
New Scenarios. Three new scenarios will be coming in Civilization V: Gods & Kings. Experience the fall of Rome, explore the medieval era, and my personal favorite: a unique scenario in a Victorian science-fiction setting.