nice point, but they'd synchronize with an offset. I doubt absolute time would be used to synchronize the videos anyway; they'd be matched by content.

Or do you mean that different frequencies will travel at different speeds, enough to make (e.g.) high and low frequencies arrive at different times? Whoa, apparently it does (http://en.wikipedia.org/wiki/Speed_of_sound#Effect_of_freque...) but seems to be a small effect.