While the 'New World' may be getting it today, the rest of the planet has to wait until July 12th. Blatant ageism! World Congress brings greater prominence to city states, and enforces treaties.
If you're someone who prefers diplomacy and culture over military actions then now is your chance to be a total jerk to the world as you rig votes to push your own agenda onto everyone.
Nine playable civilizations are added along with their leaders for Poland, Brazil, Assyria, Zulus, Portugal, Indonesia, Morocco, Venice and Shoshone. The majority are entirely new civilizations to the series. Brave New World includes all the mechanics added with Gods & Kings, expanding on them significantly.