Lets Do The Codec Question Agaaain

[Tomokka]

I have a question about the blu-ray. The question doesent have anything to do with the subject of this thread, but i didnt want to create a new one.
My friend told me that blu-ray uses mpeg2 codec, but i have always thought it used vc1 like hd-dvd does. As i understand it vc1 is better than mpeg2 because obviously mpeg2 is a lot older codec. This combined with the fact that many hd-dvd movies are getting better review from picture quality, does this mean that hd-dvd:s will always have better picture quality than blu-ray? or will blu-ray change codec at some point.