DL:
http://windows.microsoft.com/en-US/windows-8/release-preview
Yes, you can upgrade to Windows 8 Release Preview from Windows 8 Consumer Preview, Windows Developer Preview, Windows 7, Windows Vista, or Windows XP, but you might not be able to keep all of your files, programs, and settings. The following table shows what you can keep during an upgrade depending on the current version of Windows running on your PC:
FAQ:
http://windows.microsoft.com/en-US/windows-8/faq
Basically you can upgrade from CP to RP (lol) but you will loose some of the files. In any case, I will DL it and upgrade my VM.
Comments
All in all I might just skip it alltogather, win 7 does what i need it to do.
Windows 9 will be here before you know it.