Yeah I was talking about the lighting, fortnite was going to have a dynamic day and night cycle, but they UE4 switched backed to baked lighting solution. SVOGI has been put away according to Epic forum posts, but they talked about how easy it is to switch between lighting solutions in the engine.
Somebody is already working on an TressFX integration for UE4 (and is also in talk with AMD) : https://forums.unrealengine.com/showthread.php?6855-Hair-Rendering-Simulation-test