Most all the issues ae Samsung related from my point of view

My 3 year old LN40A650 Samsung is doing the same as all the Samsung LCD TV's that fade on one side.

1. Korean made TV.
2. LCD panel delaminates on one side due to age causing less light to pass through the liquid crystals.
3. By holding the top right or which ever side is dimming, press the corner of the screen and the picture will return to normal. What you are doing is causing the diodes to fire by making good contact. on the edge of the screen.
4. Fix? Keep pressing the corner of the screen and when you are fed up, buy a new TV.