I've downloaded and have been messing around in Windows Server 2008 for a while, and found some interesting information that should prove to be valuable to anyone that installs and uses this beast of an OS.
First of all, there's Keith Combs, who has a very good post on his blogsite with videos running through the most popular features in Windows Server 2008, such as Hyper-V, running Server Core, just to name a couple. I would encourage anyone to check it out.
Also, there's the standard Windows Server 2008 Technical Library at Microsoft that's packed with all kinds of information.