[lcaillo]

Burn in, aka differential phosphor aging, is a real possibility on PDPs, particularly if the contrast is left at max. Reducing it as much as possible will make it much less of an issue, if an issue at all. If, however, one leaves the same pattern on the screen continuously, you will burn a PDP. LCD direct view sets will likely be the most reliable product, with better quality DLPs likely next. Projection LCD and three chip systems in general, are IME, too likely to have problems with the light path and panels and are more of a gamble than DLP.