With television technology really taking off the last few years, most people find it very confusing when comparing the different types of television sets.
First, lets start out with the "ancient" technology of "bubble" screen TVs. Everyone has 'em. There those large, box-like, sets that weigh like 400lbs. The only conveniences of these models is the reliability, they seem to last forever. Also, they make a nice TV stand for other TVs to sit on. However, in terms of picture quality they can be described as looking through a screen door. They fall well short of today's newer TVs.
Next, comes the projection screen TVs that were really popular in the 90s. These things are gigantic. They resemble a parked car in your living room. If you're viewing the TV from an angle the screen turns black, these TVs need to be viewed, head-on. The newer "DLP" technology is related to the projection technology in that they use lamps to illuminate the screen. "DLP" TVs are much slimmer than their cousin. Manufacturers state that the lamps need to be replaced every 500 to 3000 hrs. of viewing time at a few hundred dollars a whack. That would be a huge problem for me, seeing as though I'd need to replace a few lamps a year. I will admit, with an HD signal their picture quality rivals the two heavyweights, LCD and Plasma.
So, now that we have the inferior technologies out of the way its time to compare the two flat screen heavyweights. I actually own both an LCD (40" Samsung) and Plasma (50" Pioneer) set, so I'll try to be as informative as possible. When I bought my Plasma set 2 years ago the picture quality, in my opinion, was much crisper than LCD sets. The colors were much deeper and eye popping. 2 years later, LCD TVs have certainly leveled the playing field. Both have their pros and cons. LCDs are better for viewing in a bright room, thanks to their anti-glare plastic screens. Plasma sets have glass screens, which in turn makes them much heavier. LCDs also use a lot less power consumption, something to think about for "green" minded folks. When LCDs first came out, they had what was called "lag." Meaning if someone was running across the screen, the viewer could see a shadow trailing the person. No longer the case with much faster refresh rates, lag isn't even noticeable anymore. Screen burn-in is not an issue with LCD either. However, that's thrown out of proportion with plasma, my set has been paused with no issue of burn-in. I also find Plasmas slightly less expensive per inch of screen, which I guess is something to keep in mind. So there you have it, no definitive answer! Both have unbelievable picture quality. It really depends what you're using the set for. For video games and such, LCD would be the way to go. For a room with limited natural light, Plasma would be superior. You can't go wrong with either technology. As for the older technologies, they leave a lot to be desired.