Microsoft patent: State Migration Point explained

Stumbled in to this somehow

http://www.freepatentsonline.com/y2007/0113226.html

Automated state migration while deploying an operating system
United States Patent 20070113226 Kind Code:A1
Migration of a user state from a source computing device to a destination computing device using a state migration point (SMP) is disclosed. The destination computing device may be the same as the source computing device but with a different operating system. The user state is securely stored by the SMP until the user state is restored on the destination computing device or a predetermined period of time has elapsed. Additional SMPs can be added without an architectural change. SMPs can be used to simultaneously migrate the states of multiple users of the source computing device to multiple destination computing devices. The SMPs can be restricted to migrate only the user states of computing devices with particular IP subnets. The SMPs can retain user states for a period of time after restoration in order to provide a backup, if necessary.
Check it out, i've never steered in to a patent before, when searching for documentation etc ...