I should have but I haven't had time to look into it and understand it yet, maybe a future post. There's a lot of stuff in the framework for parallel programming now, time to figure out which is still relevant.
It's pretty simple, "await/async" rewrites normal-looking code to continuation passing code the same way "yield return/yield break" rewrites normal-looking code to be a state-machine.
Jon Skeet has written a number of insanely detailed articles on it.
Oh and the PDC session added "compiler as a service", which was very interesting. You should go watch the PDC session on the future of C# and VB. It basically goes through async and compiler as a service idea.
It's a very interesting feature.