From TimesOnline.co.uk:

"Microsoft has been forced to acknowledge that a substantial number of PCs running the new version of its Windows operating system will not be able to play high-quality DVDs.

The Vista system will be available to consumers at the end of the month. However, in an interview with The Times, one of its chief architects said that because of anti-piracy protection granted to the Hollywood studios, Vista would not play HD-DVD and Blu-ray Discs on certain PCs."

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