While you can no longer download Windows 7 RC from Microsoft you can still acquire product keys. One thing to note is that you will not be able to upgrade Windows 7 RC to Windows 7 RTM or the general release on October 22nd. The upgrade editions of Windows 7 are valid only for Windows XP and Windows Vista.
For further assistance, Microsoft does have an official Windows 7 RC Support Forum located here http://tinyurl.com/9fhdl5
. It is supported by product specialists as well as engineers and support teams.
Microsoft Windows Client Team