ustream.tv video playback is broken

Steps to reproduce:

1. Try to watch the Pete's Pond video at http://www.ustream.tv/petespond
2. The page loads, but the Flash video is blank.
3. Open HTTPS Everywhere preferences
4. Disable for the "UStream (partial)"
5. Reload the video page and it will now play correctly.

I am using HTTPS Everywhere 3.1 and Firefox 20.