Still just a newbie dabbling, but thought I'd throw this in the mix not as a prediction, but more as a talking point.
We've got civs already, or announced, that specialise in culture, economics/trade, science, military (both offence and, with Ethiopia now, defence), naval/maritime and, to come, faith. What about a new civ with some sort of unique ability/unit/building concerned with espionage?
Okay, I know England's supposed to get an extra spy, but I'd still consider it more a naval-oriented civ in the game, but is there any potential civ that could be an espionage specialist.
Off the top of my head, if we didn't already have Germany and Korea, I'd suggest East Germany or North Korea would have been a good fit. Anyone else?