Heard back from YouTube. Doesn't seem as though the muting of the Barack Roll videos is going to be lifted. Seems pretty funny given that Rick Astley himself has commented on the video and that Google itself has used the video in promoting its Elections Video Search gadget. Pretty sure YouTube used it as a featured video last year as well.
A few people have asked me to reupload the video. I don't think it's really appropriate to aggravate the matter in that way. The video isn't hard to find online for those who really want to do so.
Anyhow, the follow up video of John McCain being Barackroll'd is still nice and noisy. I brought to the attention of YouTube that the video used substantially the same audio, but they don't seem to have taken any action so far.