Aaron Tiensivu's Blog

Not much more to say other than read about it here.

Wait, there is a lot to say actually - this has Viridian / virtualization bits included for the first time.

You can download RC0 here.

Unfortunately, the Vista SP1 is not public yet, but I suspect they will do a preview soon.
It seems to run very well so far. My Vista boxes now boot as fast or faster than my Server 2008 virtual machines.
That makes sense because Windows 2008 and Vista SP1 are "built" from the same tree.

I try to learn something new everyday, and this would fall under that category. I was not aware of any scripting or COM interfaces built into the Group Policy Management Console.

Wrong! There are even some sample scripts posted on Microsoft's download center.

The description of the sample scripts:
The Group Policy Management Console (GPMC) provides a comprehensive set of COM interfaces that you can use to script many of the operations supported by the console. Included in this download is a set of sample scripts that make use of these interfaces.

It looks like these are primarily for Windows Vista and Windows Server 2008.