There is an option on this tv to set it to overscan slightly or not (size 1 vs size 2). I prefer not to overscan since it takes away from some of the viewing areas. But today I popped in a bluray and noticed I had bigger black lines on the left and right sides of the TV (like on some regular HD channels that don't actually take up the ENTIRE screen, but are still HD), so I put it in overscan size, and make the black lines smaller (picture was taking up the entire screen), and then put it back to overscan off and those black lines did not come back.
I hope that makes sense because I don't know how else to explain it. Anyone know what I'm talking about?