I really don't know how to phrase this question, but you know when you go to the higher end section of HD TV's and there is a blu ray playing, and well, it just looks as if everything is happening right in front of you? It doesn't feel as if you're watching a movie.
I'm in the market for a 60" plasma, in particular 1080p with a 600hz refresh rate. Now, I don't know what to look for when it comes to making the picture really pop.
Looking at LED's, I notice a huge difference between a 60 and 120hz, it has that "look" i was trying to describe above.
the difference between non hd video and hd video is definitely the largest difference. not all video played in stores is hd.
leds and ccfl are just backlight types for lcd panels. generally speaking they are about equal in performance but leds save you money. on some high end panels however the leds are arranged in a grid instead of edge lit which can improve contrast with zone-backlighting instead of full-panel backlighting dimming.
plasmas have the highest contrast but have had a bad track history of expensive repair and high maintenance costs. personally i wouldnt touch one with a 10 foot stick but to each their own.
the input signal is still going to be 60hz. the tv just fakes in the extra 60 frames for 120hz. this can smooth out the video but does not work well when connecting game devices or a pc.
keep in mind that some panels will look better than others. there are different panel technologies at work.
SSDDX is on the right lines but in addition to this, movies were created specifically for displaying in 24Hz. Having a display that claims to do 400hz will just turn the movie and make it look stupid. If you put an Action movie on a high end TV and turn up the "motion enhancement" up to the maximum setting. It will run very inconsistently, resulting in screen tearing on some displays.
Plasmas in a dark room with no light shining on the screen, produce a better colour tone and deeper blacks than an LCD.
LCD TVs cost less to run than Plasmas, but if you want a better, more realistic and a quicker responding panel, its better to go for Plasma. What ssddx said about high repair costs is true for BOTH LCD and Plasma. If the screen breaks, it often is more expensive to repair the TV than replace it.
As for manufacturers, DEFINITELY go for a Panasonic, especially for plasma. In particular, go for a Neo Plasma (G series and up) which combine Panasonics quality with the know-how from the engineers which used to work on the Pioneer Kuro TVs 4 or 5 years ago. If this is out of budget, go down in screen size. I'd much rather get an excellent 55" plasma panel as opposed to an average 60".