I would like to add one more to the "Cloudy" side of the argument.
I noticed it on Day One of purchase when I was watching the Cinemax HD marathon of the entire Star Wars series. I would notice it on any space combat scene.
If it's not a night scene or a black screen, the picture's beautiful. But when watching, say, Adult Swim when they always cut to the black screen with white text bumpers I would see it plain as day.
I'm going to try and de-stress it by laying it flat on its face for a couple of hours and see what happens. I'm still within the 30 days at Video Only and I really think this is a "defect" and not a "usual effect of LCD panels". But from the sounds of the folk on these boards, if I swap it out for another, I think I'm going to get the same problem...and risk getting a worse panel with dead pixels (this one's clean otherwise).