"Even though Microsoft officially supports HD DVD (see related blog, the company isn't sure that Vista will include native support for the next-gen DVD format.
Vista, coming in the second half of this year, is the successor of Windows XP, and includes basic and premium versions. In particular, Windows Vista Home Premium will replace Media Center Edition, and of course everyone is excited about using high-definition DVD players with MCE.
But they might have to wait. It's possible that Microsoft will rely on third parties to write the appropriate applications for high-def DVDs after Vista is launched. Or Microsoft might do it themselves, before or after the Vista launch.
A Microsoft spokesperson says, "Vista's architecture will recognize both HD DVD and Blu-ray DVD; however, current plans for Media Center support of either of these formats is unknown at this time. We do know that there will be a great HD DVD and Blu-ray DVD experience for Media Center either at Vista launch or soon after as either an extensible application or natively in MCE."
So will it or won't it? Only time will tell on this one but I should imagine that there will be some support for HD DVD eventually, if only by a windows update at the worst. Microsoft make some good points though - will HD DVD really be so popular that it will need native support in the new operating system upon release?