Hello Bob,
In the past 2 yrs, 64-bit Vista was causing issues. But in the past 6 months, I have been on numerous customer and test systems running 64-bit processors with both 32-bit and 64-bit versions of Vista and Windows 7. And, I am happy to report that I have encountered no more issues. Even on Hewlett-Packard 64-bit machines!
So, I believe the 64-bit issues (nothing has changed with BD) have been fixed by manufacturers and Microsoft. And I expect no issues with 64-bit machines going forward, on either Vista or 7; running in either 32-bit or 64-bit mode.
With that said - something new could always pop up. But, many customers have installed BD in the last 2 weeks on 64-bit Windows 7 machines and experience no problems other than the need to install the MS hotfix mentioned above in the FAQ to support Petey.
Let me know if you find out differently please. My Windows 7 box is still on order! 
Jeff |