John is still correct. RC1 was Vista Ultimate.
You can purchase a Vista Ultimate full edition of the same platform you have now and perform an upgrade.
For any thing else, you need to preserve your files and settings with the Windows Easy Transfer wizard that comes with Vista. You will have to reinstall your apps.
I am sorry RC1 build 5600
You don't say what version you are running, but if it is the beta2 from your subject line, no. Since the CPP were Ultimate versions no other version would be available to update, and you would require a full version to do any upgrade.
Look here for all the information on the systems available
http://www.microsoft.com/windowsvista/getready/default.mspx
When my Vista evaluation period is over and it is time to install a new Vista operating system can you install over the Vista beta or do you have to reformat the hard drive? What types of operating Vista systems are there?