I work as a broadcast technician for a college, and I thought I'd make a comment about the tie that Senator Mccain chose to wear to the debate.
A Moire pattern, as it pertains to video, is created when certain patterns are sampled incorrectly in video. Patterns that have small lines that are spaced close together, such as houndstooth patterns, create bands of light and dark that resemble movement that isn't really there. As the subject wearing the piece of clothing moves, it creates a sampling error with the camera that becomes quite noticeable. Bright colors, especially reds, make the problem more noticeable.
If you look at the tie Mccain wore to the second debate, you will see a textbook example of a Moire pattern. Any good producer or video technician should have caught and corrected this issue. Mccain's handlers should know about this with the amount of appearances he makes on TV.
I don't think that any of this is especially significant, but I thought some of you might like the explanation of why his tie appeared in the video as it did.