..the name brand HDTVs emply technologies to help combat this. It's still prudent to be wary of static images during the break in period just to be on the safe side. Although some of the BB house brand panels may be manufactured by Samsung/LG, etc., they may not all have the same technologies to prevent burn in or IR (image retention). There are some helpful threads on burn in, as well as links to break in DVDs you can make to speed up the phosphor wear process per se. Check out the plasma sub-forum @ AVS forums.
Just yesterday our family bought our first flat panel TV. Its a 42 inch Insignia Plasma (made by the same company as Samsung is what I was told by the people at best buy).
I've heard you should be careful about "burn in" on a plasma tv for the first 200 hours of use and not put the contrast on the tv above 50. But I've heard from other sources that "anti burn in features" in TVs will prevent this, and it is not necessary.
Do I need to worry about burn in on my new tv? Should I keep the contrast low, even though the picture looks much better on a contrast setting around 70 or 80?