Deep Color is basically BS marketing at this stage. Neither HD DVD nor BD have ANYTHING in the specs to allow Deep Color encoding so they cannot benefit from this tech. When a device (either displays or players) says it supports Deep Color, all it is saying is that the HDMI connection supports it. At this point, no consumer displays currently can even display Deep Color, and they ALSO are only saying that the HDMI connection can handle it which means that the HDMI version is 1.3.
Again at this point it is just marketing BS and IMO, VERY misleading to not state that it is only the connection that can handle it, but the receiving device itself cannot do anything with a Deep Color source if one existed.