PC World has written an article about PVP-OPM, this is a new protection that you will need to view copy righted high-definition video in Windows Vista. If your monitor doesn't support HDCP then you will not be able to see the video. And unfortunately currently close to zero monitors support this feature, although manufacturers are planning to release some soon.
Unfortunately, PVP-OPM will also shut out plenty of law-abiding video watchers whose current displays aren't future-proof. To comply with the film industry's protection scheme, PVP-OPM employs HDCP technology to determine whether graphics boards and displays are allowed to output and display high-def video. If HDCP sees a blocked display (such as a video capture device) or one that does not support HDCP (including any HDTV with only analog connectors), it prevents output or reduces the video resolution until the offending display or protected content is removed from the system.
Read on over at PC World to learn more about this issue.