SPAAAAAAAACE!
Like all good franchises, Civilization has finally (well, again) realized that space is awesome. The announcement buzz around Beyond Earth makes it clear that, while it won't necessarily change the basic gameplay mechanics of Civilization V, it will introduce some very interesting wrinkles regarding AI interaction and game goals.
For me, the best parts of Civ 5 were the most sci-fi parts -- stealth bombers, nuclear subs, death robots, and of course launching into space. Pretty much everything about Beyond Earth sounds like the best part to me.