I got given a Samsun 40" D5520 which replaces my 32" LCD Panasonic and I'm a bit disappointed. Even after some basic calibration (no full colour adjustment or 10-point WB available) the picture is sometimes a little foggy, and some images seem to have purple fringing at times but I read this is very common with LED type TVs. Obviously having a bigger telly shows all this up so much more. I need to do some more checking but I was watching a film on BBC HD and it had some ghosting in some scenes, I pulled out my DVD copy and the same ghosting appears so I'm not sure if it is my TV or an issue with the actual film (will need to check on another tv I guess).
I do find that you get the best picture with all the software options turned off - but to appease the wife I have turned on noise reduction on sky HDMI as she was complaining about the SD picture.
I don't have a blu-ray player so can't comment on that quality.