This thread is old, but it comes up when searching for "erase plasma burn-in", so i thought I would add some truth to it for TVs of 2012.
I love my Panasonic VT50 and I love my video games. So I was conflicted and torn when I noticed the Call of Duty HUD burned into my beloved plasma. I can't stop gaming, but I can't give up Panasonic's excellent plasma. So I went to the all-knowing Web to find a solution. While everyone seemd to say that burn-in was a thing of the past, I had the undeniable proof that it was not. Many claimed that running full-screen video for hours would help, so I tried playing The Dark Knight Rises on a loop for about 48 hours. Alas, the burn-in had not even faded.
Another site mentioned that I should try running a continuous loop of digital snow static at max brightness and contrast for four times the amount of time that the burned-in image was displayed. So I went to the Call of Duty "barracks" to see my time played....5 days and 20 hours...140 hours. Meaning 560 hours of continuous playback to remove the burn-in. At this point, I would try anything, so I bunred a DVD with the digital snow pattern, set brightness and contrast to max, and let her rip. I am so very happy to say that about 50 hours later, the burn-in has faded about 75%.
I figure another 10-20 hours and it should be gone, much, much less than the 560 anticipated. So that would mean running the DVD about half the time the image was on the display.
I hope this helps anyone out there with the same problem. Don't despair and don't cry (b/c i did), just do as I did and you'll be fine.
65" Samsung F8500 - Marantz SR6009 - Oppo Blu-Ray Player
2 KEF iQ90 L&R - KEF iQ60c Center - 4 KEF iQ8ds Di-Pole Surrounds - KEF PSW2500 Sub
Xbox 360 - Xbox One - PS4 - ASUS G751