I have a TeraStation Pro II (rackmountable) in production, and I'd really like to upgrade to a Windows 2008-based domain, so this may be a huge problem.
I emailed Buffalo support about this and got this message:
Currently, Windows Server 2008 in an unsupported OS for the Terastation Pro II. I have talked to customers who have gotten it to work. However, we here are unable to aid you with it.
I'm going to receive a new higher capacity TeraStation Pro II soon to function as a backup NAS server, but before I put it in place, I'm going to test it in our lab environment on Windows 2008. I'll post the results here.
Also, if any of you are having trouble with the NAS in Windows 2008, this might help you out:
http://support.microsoft.com/kb/942564
It's a security risk, but I believe no more of a security risk that what is currently in Windows Server 2003.