Today, Microsoft released Windows Server 2008 Hyper-V RTM (release to manufacturing). This is the real thing, folks! No more beta. This is much earlier than the August 2008 timeframe that Microsoft announced when Windows Server 2008 was released in February.
Click here to download the RTM version of Hyper-V. In 12 days you'll be able to go to Windows Update from your Windows 2008 server and it will be listed as an optional component. As you may know, the Windows Server 2008 installation bits are cached on the local computer. When you download and install the new version of Hyper-V it will update the local cache. If you ever uninstall and re-install the Hyper-V role, it will reinstall from the updated cache (the RTM version). This means that once you update a server with the new version, you won't need to update it again (unless Microsoft releases a newer version).
We should see new Hyper-V virtualization supportability agreements for some Microsoft products, like Exchange Server 2007, within the next 60 days. System Center Virtual Machine Manager 2008 which offers both Hyper-V and VMware virtualization support should be out soon, as well.
On a side note, Rand Morimoto and I have finished writing "Windows Server 2008 Hyper-V Unleashed," published by Sams Publishing. Look for it in a store near you.
Now, go forth and virtualize!