Just got an email from Connect this evening announcing the availability of build 06.00.1371. From a quick read it looks like it’s going to be possible to upgrade from the Beta 2 build. There are lots of warnings about making sure that all of your data is backed up, and this is a great opportunity to remind everyone that WHS should NOT be the only place you are keeping your important files. I use FolderShare to sync all of my important data to a partition on one of my clients (you can exclude this folder from your backup configuration to avoid overly large backups).
I’m downloading the new build now. Can’t wait to see what has changed (going to go look at the release notes now…)