Even though Vista on a 32 bit machine will recognise and be able to use both HD DVD and Blue Ray drives it will not support commercial HD movie playback. The reason for this? To quote MS source:
The surprising disclosure was made by Senior Program Manager Steve Riley during a presentation on Windows Vista security at Tech.Ed 2006 Sydney today.
“Any next-generation high definition content will not play in x32 at all,” said Riley.
“This is a decision that the Media Player folks made because there are just too many ways right now for unsigned kernel mode code [to compromise content protection]. The media companies asked us to do this and said they don’t want any of their high definition content to play in x32 at all, because of all of the unsigned malware that runs in kernel mode can get around content protection, so we had to do this,” he said.
More at: APC Vista Report
Previously posted at blog.Solidsoft.com