Apparently, the latest Harry Potter DVD was manufactured under a low transfer quality so people would decide to upgrade to bluray. I haven't received my pre-ordered DVD in the mail yet so I can't say for certain, but the folks at the DH pt2 board who do have the DVD have all said the same thing. They purposely made it sub-standard quality so people would go out and purchase bluray players and the blurays themselves if they want to experience the full quality.
I of course posted a lengthy post regarding how bullcrap this is, how some people can't afford to buy blurays, the players, or even HDTV's (I still have a 27" CRT). WB is cheating the good DVD buying consumers out of quality product in order to get people to upgrade and I am outraged.