ArsTechnica reports that some users who have downloaded Windows 7 from the early release outlets (Microsoft Connect, MSDN, TechNet) can't get keys - and thus can't activate their downloaded copies.
Here's what Microsoft is saying about the glitch (via ArsTechnica):
We've had some reports over the last few hours where customers have been receiving errors when requesting Windows 7 Beta product keys. We can confirm that we are having trouble distributing Windows 7 Beta product keys right now. Since Windows has a grace period built in before a product key is required, please don't hesitate to download and use the Beta without the product key. We will post information here as soon as this is resolved.
Like ArsTechnica, we'll also be keeping an eye on this problem and will let you know when it's solved.
While folks like me are warming up our broadband connections and our browsers for the official release to the public Friday afternoon, if you've downloaded Win7 beta from MS Connect, MSDN, or TechNet, hit Comment and tell us about your experiences so far.