Facebook released a demo video of their Surround 360 technology a few days ago, called "Here and Now": https://www.facebook.com/facebook/videos/10154659446236729/ Apparently they are using their proposed cubic mapping perspective for this. Can someone familiar verify that?
When on my Gear VR and I rotate my head, I notice a slight quality improvement. So also, does anybody know if they are using an adaptive view-aware streaming such as DASH or something for that (which will be impressive)? I am assuming it is not first downloaded and played, so maybe this is not due to the rendering.
Facebook uses pyramid encoding. They put a sphere inside a pyramid so that the base of the pyramid is the full-resolution FOV and the sides of the pyramid gradually decrease in quality until they reach a point directly opposite from the viewport, behind the viewer. That explains why, when you turned your head with the GearVR on, you noticed a quality change. They don't use MPEG-DASH, yet.