Microsoft are hosting an entire track giving technical insight and encouraging feedback at the Blackhat conference. For those of you who (like me) aren't able to go to Las Vegas for the conference it's worth watching out for both webcasts and the events in Europe and Asia.
There's more information available on eweek and also on the new Windows Vista Security blog.Austin Wilson (Director of Product Management for Windows Vista Security) will be there an he's keen to receive feedback as he explains in his post about external security assessment which reads like a who's who of reputable penetration testing companies.
The TechJournal discusses both Blackhat and Bluehat
I think it's rather interesting that Dan Larkin from the FBI is presenting the keynote given that this conference started out as a gathering of people who were intent on finding the limits of both system and application security.