Where? The lighting is as flat as roadkill. If there is GI it must be a very, very primitive and basic implementation that harms the game more than it helps.
Indoor scenes now use static lighting which doesn't bounce colour onto other surfaces the way GI would.
Unless your talking about a day and night cycle, which isn't Global Illumination. Global illumination is used to correctly bounce light across surfaces in a realistic way instead of the light just hitting the surface in a flat way which this game does.
I don't know mate.
Exactly, even with the flat lighting the game looks stunning, just annoyed that they showed a more advanced lighting system literally 90 seconds before starting the game.