A European MVP had this to say on Warlords of Draenor as the next expansion.
https://twitter.com/Proenix00/status/397606126427975680
Osiris: Is Warlords of Draenor a WoW expansion, or not? (¿Es o no, Warlords Of Draenor, una Expansión del WoW?)
Proenix: It is (Lo es).