The key code will only work with the RC. Beginning on March 1, 2010, your PC will start shutting down every two hours. The RC will expire on June 1, 2010.
When you install the final version of Windows 7, you'll need to do a clean installation. So plan on backing up your data then reinstalling your applications and restoring your data.
i think some one will come out with a work around b then anyway tho, if there isnt one out already. not sure how able we are to talk about that on the forum tho...
im not saying that, im saying if some one comes up with a key to bypass the RC's shut down in the process disabling windows updates and things like that. so you can still use RC past june 2010