As far as I know you can update through Windows Update and will install fixes for the beta... I could be totally off though...
This might be unrelated - but I had a beta version of Windows Server 2K3 that when updated - the version numbers did not change until I installed the first major SP - then the version changed when updated.
I am not sure if they are going to push us the latest ui improvements but mine updated itself a few days ago. I still show build 7000 though. Nigel