Well written paper by Peter Gutmann: A Cost Analysis of Windows Vista Content Protection.
“Windows Vista includes an extensive reworking of core OS elements in order to provide content protection for so-called â€œpremium contentâ€, typically HD data from Blu-Ray and HD-DVD sources. Providing this protection incurs considerable costs in terms of system performance, system stability, technical support overhead, and hardware and software cost. These issues affect not only users of Vista but the entire PC industry, since the effects of the protection measures extend to cover all hardware and software that will ever come into contact with Vista, even if it’s not used directly with Vista (for example hardware in a Macintosh computer or on a Linux server). This document analyses the cost involved in Vista’s content protection, and the collateral damage that this incurs throughout the computer industry.”
So, it looks like even though you may be forced to buy premium hardware to enable you to run Vista, you may still not be able to make use of it.