Probably just an error. I had the same thing happen once on Vista and 2 maybe 3 times on XP. If reloading the window doesn't help, try restarting and it should show.
...and the rumor mill starts... You should expect to see a lot of blank pages like that when downloading from a 56k modem. Wait until SP1. It is most likely that MS will block the leaked keys at that time. BTW, on a more (not so) serious note, I downloaded "The Hangover" off Demonoid and watched it with my girl and a good buddy last night... ROFLMAO!!! Almost pissed my pants...although that may have been due to the beer...