I purchased an LG PK550 in early December and started noticing/researching the horizontal line bleeding problem in January. The line bleed was ALWAYS on my tv I just didn't notice it right away since I wasn't aware of it nor was I looking for it. I DID notice it though and wondered WTF to myself before actually researching or hearing of the issue. My first HDTV (before this current LG Plasma), was just a generic 720p plasma and that TV did NOT have any line bleeding. The IR was pretty bad but that was my only issue with the old TV.
Anyways we are now in mid-April and I am just now getting my TV looked at/serviced. I have the 4 year product service plan through Future Shop but since the TV is in it's first year I had to contact LG. They sent out a technician from a local repair shop who handles repairs for LG and other manufacturers. At first the guy tried replacing the power supply, then the mainboard...both to no avail. This was yesterday, and he took my TV to the shop and gave me a loaner LCD to use in the meantime. He or his superior had both apparently never experienced this line bleeding issue...which is quite surprising as many plasmas have this problem just by doing a simple Google search.
I just have a feeling that the repair center is gonna say either tough luck or it doesn't seem that bad, and not do anything to help me out. The line bleed IS very evident, but again you have to be watching certain programs (like The Office, Wrestling/Boxing) to be distracted by it. However, now that I know it's there, I can notice it in almost everything I watch if I look for it. The menus on the TV as well as PS3/Xbox 360 make it very evident, as does the green preview screen with the white text when watching previews on Blu-ray.
If the repair shop doesn't help me, obviously my next step is to call LG. I have read this entire thread and a few others and there doesn't seem to be any acknowledgment of this problem by the manufacturers OR any solution. I knew when buying plasma I had to deal with Image Retention & Glare, but the benefit of smooth motion, more accurate color reproduction, true Blacks with no light leakage & price vs the LCD far outweighed any of those negatives.
I have attached some pics for reference.