It's July 1, and those of you running the Windows 7 Beta may have noticed your machine shutting down every two hours. This is not a bug...it is Microsoft's way to get you to move over to the Release Candidate Code. Better do it quickly! It gets more severe starting August 1.
The RC will begin its shutdown routines on March 1, 2010. The commercial release of the OS will be October 22, 2009, so you should be in good shape. That is plenty of time to get the final product. One note though...it isn't an easy upgrade from beta to RC. A clean install is recommended (unless you had the foresight to run the beta in a virtual machine, that is).