Bumping this thread up to current 01/14.
The date of manufacture of my UN55D8000 is March 2011, also the date of purchase. Manufacture according to the name plate was in Tijuana, Mexico although I expect assembly was there and the parts are Asian. November of 2013 is when issues appeared to me- call it 2 years and eight months. I do have conditioned power through an APC battery back up and the only source connection used on the Samsung is HDMI in to the ARC port from an Onkyo TX-NR809 HDMI out. The Onkyo sources FM, XM and internet radio internally and pushes video accompanying its internal sources and routes video from external sources DirecTV HD DVR, HTPC w/ Radeon 7770 vid card, Panny 3D DVD player, and PS3, all HDMI in to the Onkyo. There is no difference in the image issues dependant on which source is fed through the Onkyo and the Samsung Smart Hub and Samsung onboard menu are affected as well (picture below) indicating that external inputs are not causal. Any screen shot will show the same display failures.
Sometime around Thanksgiving 2013 my unit began to behave as described above. There are additional anomalies present including white horizontal lines (picture below) and blotching and ghosting. I was able to correct my issues sometimes by either applying moderate hand pressure to the edge of the screen near the top left (facing the screen) or by disconnecting power if the pressure trick did no good. I put a 6 outlet surge arrestor at a convenient location and plugged the Samsung into it to save the trip behind the set.
It became more frequent during December but with the holidays I didn't deal with it. Last week I called Square Trade who I had paid for an extended warranty. After I emailed photos of the banding they authorized a repair and the tech is coming tomorrow, 1/7/14. In the meantime they had a new T-con and a harness fedexed ahead. Clearly their first effort is going to be to affect repair in the same manner others have. Cost impact I expect drives the repair effort.
I will show the tech this thread although if he is Samsung authorized I bet he is well aware of the issue. As others have stated, at the price I paid for this, threeish for a flagship product, this is a bad turn of events. We have an eight year old Vizio hanging on the wall in our bedroom that cost less than a third and has been faultless. It doesn't offer the quality of picture or options the Samsung does, but it doesn't offer these screenshots either.
I will update as events unfold.