Robert says: If you left a static Uno hand on the screen for three days straight, it might leave a permanent mark (due to uneven pixel wear)--more so with a brand-new plasma screen with "fresh" pixels.

I always suggest running a newer plasma in its "movie" or "theater" picture mode for the first 100 to 200 hours, as this is a plasma screen's most sensitive period. Once the plasma screen has aged a bit (hopefully running full-screen video and not 4:3 material with pillar bars), that kind of afterimage is less likely to happen.

You did the right thing, though, by running the TV's image cleaner. It cycled all the pixels a few times and removed the traces of (non-permanent) after-image. You could have performed a similar function by playing a movie (full screen, not letterboxed) or tuning to an empty channel (filling the screen with snow).

For day-long gaming sessions, it is practically impossible to cause any permanent image retention ("burn-in") with a plasma display. For a weekend-long gaming bender, you may want to keep the TV in its less-intense movie mode (and don't forget to turn the console off at night!).