Volume Fog had a few issues trying to work for every kind of games, it was a bit too soft, had flickering and noise on high contrast, reconstruction was very ghostly specially if things were moving in the scene, didn't perform well with many lights.
It's been rewritten with state of the art reconstruction technques and uses the same frustum tiled lighting system now.
This looks better and runs better in most cases, especially on scenes with many lights, on my testing I'm getting 250fps (0.4ms) on Datacore now, around 180 (0.55ms) before.
