Like the manual transmission, plasma seems to be the ill-fated, but superior technology. I wanted to relay a recent experience that might unclinch some toes of prospective plasma owners.
I have owned countless plasmas of numerous manufacturers from Pioneer to Vizio. Samsung and Panasonic have been my manufacturers of choice and i have never had a reliability issue with either. Some buzz to varying degree, but I have found reliability to be superior to their LCD equivalents.
While at BestBuy, i did my usual clearance item dumpster-diving and found an open box Panasonic TC-P50GT50 for a good price. The home theater rep warned me that i had "burn-in"...in fact someone appears to have watched PBS kids shows heavily, rendering slightly lighter rectangles outside of the 4:3 area and an "E/I" logo in the upper right side. Big Bird dominated this plasma.
I checked the hours and it had roughly 160 hours, which is all but virginal in my book. I took it home and displayed an inverse image of a 4:3 box on a break-out slide. It alternated light gray to white for the outer boxes and dark gray to black for the middle. I used MS paint to create a dull circle of the logo that remaind black the entire time.
After roughly 36 hours of "treatment," the "burn-in was all but gone on green screens. 24 hours later it was entirely gone.
The "burn-in" probably would have faded on its own over time with just regular viewing, but I figured i would experiment with a method i had used in the past.
Hopefully this gives people some more confidence that while image retention can be vexxing, it is far from a permanent phenomena unless you really, really abuse a display.