Todd Spangler writes "Comcast, like every video distributor, compresses its digital video signals. But to fit in more HDTV channels, Comcast is squeezing some signals more than others. The cable operator claims it is using improved compression techniques, so that most subscribers won't see any drop-off in picture quality. But A/V buff Ken Fowler claims the differences between some of Comcast's more highly compressed channels and Verizon's FiOS TV are indeed noticeable. He's posted his comparative test results on AVSForum.com — and the results are not pretty."