The most popular area of discussion I experience regarding Microsoft @ InfoSec related to Bitlocker (a feature of the high-end SKUs of Windows Vista) - formerly known as Full Volume Encryption and Secure Startup.
There's some interesting discussion in the blogosphere. *** Edited to fix broken link ***
If you aren't familiar with Bitlocker then read this if you get a mo(ment)
Do you think Bitlocker will be useful in YOUR production environment - your comments are appreciated.