Some sites out in the community have begun posting links to the Customer Preview Program (CPP) download of Windows Vista RC1. Before you jump up to get your own download of RC1, please bear in mind these facts:
If you previously registered for the Windows Vista Beta 2 Customer Preview Program 2 and received a product key (PID), that key will work for the Windows Vista RC1 release as well. You need not re-register; you will need to download the RC1 ISO image, however. Microsoft has just today begun sending download links via email to previous Customer Preview Program participants who registered for Windows Vista Beta 2 back in June. Not all emails are being sent simultaneously, so there may be a few hours' delay in delivery of yours.
The Customer Preview Program has yet to open back up for new registrants. Therefore, if you do not already have a PID and were not part of June's Beta 2 CPP, you will need to wait until the CPP opens to the public in order to register for a PID and install RC1. I expect that this will occur in the very near future, so keep watching this blog.
In other words: if you choose to download RC1 now and weren’t part of the Beta 2 CPP in June, you must wait until the CPP is opened to the public before you'll be able acquire a PID that will enable you to install RC1.
Please be mindful of the above when making your decision to download. I must confess that while I and everyone on the team certainly appreciate your enthusiasm for downloading, registering and testing RC1, posting comments to this or any other MS blog asking for product keys won’t get them to you any faster. There's nothing I can do to accelerate the public availability of RC1; but, I can keep you informed, and pledge to do exactly that.
So, once the RC1 Customer Preview Program officially opens up to new registrations, you can expect a post here letting you know. Thanks for your patience in the interim :)