Well that would seem to match my request for examples, though I find it interesting that he had only two examples and refers generically to "numerous other posts on various technology forums" but provides no details. You can find innumerable posts about burn-in and how to avoid it but few about victims of it. I also suspect (with admittedly little evidence) the primary "victim" here was not playing Guitar Hero for just a few hours to produce burn-in. We're missing the details of what the two affected plasma owners did to cause burn-in. If you play guitar hero for 16 hours a day, day after day with no alternate content, why yes you might have a burn in issue.
I'm also struck by the quotes from the contact at Panasonic:
"There is no such thing, almost, as burn. You have to as an end user almost intentionally try very hard to burn a set," says Barry Murray, director of marketing at the audio-visual group at Panasonic Canada Inc.
Short-term image retention can happen, Murray says, but it usually goes away after watching a few minutes of full-screen video.
"It's fairly common but 100 per cent reversible just by watching other video programs."
Have there been posts from users in this thread or elsewhere on the Plasma forum at AVS? You'd think with a problem purported to be this serious, impacted consumers would show up here, at least occassionally...