Windows 2008 RC0 and Windows Vista SP1 beta out today

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.