As you're probably already aware, Hyper-V was released not too long ago. There are a number of resources available to help you with your adoption and support of these new virtualization features in Windows Server 2008.
One piece of advice, when doing a clean install of Server 2008 we'd highly recommend running through and downloading all of the Windows Updates that are currently available including the RTM update of Hyper-V. When running through the add new role, Windows will install the latest package it has available in its repository, so you'll want to make sure the latest is downloaded before you install for the best experience.
Here is some additional information about the install process and where to get the updates. After you've run the updates and started using Hyper-V, you may want to take a look at this PowerShell management library which makes easy work of many Hyper-V tasks. Just paste the library into your PowerShell profile and you're good to go. Trying to debug in Hyper-V, take a look at the following post to help you along.
Finally, be sure to check out the Virtualization team blog for the most up to date information about Hyper-V and other virtualization news.