Got a copy of this from a co-worker to try out. Installed it on my extra machine with a 500gb drive. Install was simple - it actually puts Server 2003 on first then a nice GUI wrapper over it called home server. Just like Vista it has all the SATA drivers already so no need to dig out a floppy and do that whole dance.
Right away after boot up it warns you to access the server console from your desktop and not the server itself. I guess the idea is to load WHS on the computer and then manage it from your desktop. It comes with a connection disk that you run on all your workstations. You set up passwords for each user and that's about it for setup.
The feature are simple but nice - it does a backup each night for each PC, it creates public folders for videos, audio, files, and pictures. And it creates private folders for each user on the server. You also get a nice remote access page you can get to from anywhere on the web, giving you access to your files. You can upload remotely too. So far I am impressed with how simple it is.....but not sure if it's work purchase at $170.