-Norse having to kill to gain favor
-the addition of Starcraft-like specialty units (the myth units) in general
-the move to a 3-civ org in which each civ is very different (again like Starcraft and unlike AoE or AoK)
-many of the UI changes
-and the potential (maybe) for ships to be generic and extensible.
But I have to say that my
H, C, C, H, C, C, H, C, C, H, C, C