Follow up on screen problem
I haven't looked at this thread for a long time so I'm posting a follow up to my post on 12-13-13 when I had the problem with the screen on my KD-34XBR970.
My problem went away and has never come back. I only did two things.
1) I played with the tilt correction and vertical correction (page 46 of the manual) which apparently sometimes needs attention after moving the TV.
2) I unplugged the TV and let it sit for a day before plugging it back in and turning it on.
I had been moving the TV around before the problem started but I can't say for sure what caused the problem or why it went away.
All I know is that it's cured.