On my rMBP I don't believe its image retention. But when I transition with 3 fingers I can see that in the middle there's a dark area thats in a form of a line. You cannot tell when the images on the screen are still. But when I transition I can see there's a slight dark area. I'm not sure what I should do with it, it's not a major issue I can't live with. It just bothers me but I really don't want to go through the return/exchange hassle. Samsung screen btw. EDIT: More words to describe it is, a very very vague blemish only noticeable when on a white background and in transition.