I converted my office fileserver to Windows Server 2008 (WS2008) a while back and I've never been happier - WS2008 is my favorite product ever.  Nicely modular, pretty much everything turned off by default and some great tools for enabling just the components your need for a particular role.

There is one more step I've been wanting to take and that is to enable the Hyper-V role and convert my fileserver over to just one virtual machine on the box, so I can set up other VMs on the same box.  Today, I was excited to see Microsoft Releases Hyper-V on CNET.  Here is a summary of the key links (note that it is only available for the 64-bit versions of WS2008):

Check back with my and I'll let you know how things go and share any tips I have for what to do or not do, as well as my review of how easy/hard it is.

Regards ~ Jeff