Still not sure about the plasma burn in debate. I've always been warned not to get plasma because of the burn in. Though it seems the newer tv's don't have this issue?
I'll have to assume the people warning you about burn in on plasmas don't actually own plasma tvs.
As mentioned above, plasmas as "new" as five or more years old don't really suffer from burn in issues. Knocking a reasonably modern plasma due to fears of burn in is like saying don't buy diesel cars because they smell. That's outdated information that has not applied for years.