We have a Sony Grand Wega KDF42E2000 and about a month ago, I noticed some weird discoloration on the top and bottom of the screen. My wife couldn't see it, but it was bugging me. Now that we have the Wii, the problem is really noticeable. I love the TV and I hope it can get fixed. The current suspect is the optical block. More on it when I can get it fixed.
Here are some photos that show the issue:
Update: The repairman came on Saturday armed with a new optical block. He had me turn it on and show him the problem. He only had to see the top of the screen and instantly had me turn it off so that he could replace the optical block. He was very knowledgeable, and I liked that. Of course I watched him do the repair so next time I can do it on my own. I am very glad that the unit was still under warranty.