I am at a B&M store over here and we just used a calibration disc for all our plasmas (ED and HD). You will be amazed at what one of those discs can do for ya. When they are calibrated the same you can definetly tell the difference between both. Even when they are not calibrated the same you can still make out the resolution difference. Some, however, will say they cannot tell the difference between the ED and HD. I beg to differ.
Most people agree that at normal viewing distances the EDTV very closely approaches the HDTV with HD content. If you do a search you can find arguments ad nauseum spanning the range from "no difference" to "night and day". Obviously you are not in the "night and day" camp. As for where to get HD content, most the stores run HDNET channel, available from DirectTV. It's mostly a demo channel in my opinion, but the video quality is as good as it gets. You need an HDTV tuner for the dish guys. You may or may not also get HD over your local cable. Again, a special tuner is required. HDTV content is spotty at this time and there likely will be an extra charge. You can find more about available content on the HDTV Programming Forum. A third option, available in most urban areas, is over-the-air network broadcasting in HD. This is what I have. It requires an HD tuner and antenna, but is otherwise free. The networks all have a couple hours of prime-time HD programming each night, major sporting events, etc. Check out the various HDTV forums.
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