Great question! I too was looking for more detailed guidance in deploying this groundbreaking and "Killer app" feature for win7 and ws2k8R2 servers. This new feature basically makes and uses a "touchless" VPN solution. I would have killed for this years ago when i was at a large company with alot of unskilled road warrior remote users. They would always give me the same speech..
"Why can’t i just turn it on, log into windows and just auto-connect?"
that feature and day has arrived since that is exactly what Direct Access (DA) allows a user to do. As soon as you have an internet connection , BAM! Auto authentication using IPv6 and certicates to unsure an IPSec encrypted private connection without a single prompt for credentials!
Click the link for the IPD – Infrastructure planning and deployment guide!