Burn-in on plasma is a problem starting with EDTV and continued with older generations of HDTV. The new generation of plasma still have burn-in issue due to the properties of phosphor based panel. But since a couple years ago, manufacturers have been working on ways to prevent burn-in. Samsung has the built in "Screen Burn Protection" in the setup menu with Pixel Shift and Signal Pattern. Having said that, most newer generation plasma TV (like yours above) will probably never have a burn in problem.

Note that you might get temporary ghosting but this is different than burn-in. Burn-in is damaged pixels while ghosting (ie after static image for an hour or so) can be fixed easily.