Mark Curphey here.
I am delighted to say that Threat Analysis and Modeling (TAM) 3.0 Beta is now live on MSDN. You can download it here.
RV posted an initial mail about some features yesterday here. RV will post series of screen casts on new features this week.
As this is a beta build we have set up a Connect site that enable you to submit bugs and feature requests. You will need to register at connect.microsoft.com with your Windows LiveID and then submit bugs here and feature requests here.