or you had it on a static image, or a portion of the image was static, for a very very long time.
With modern LCDs (heck even with most older units) it would take hundreds, if not thousands, of hours for any sort of burn in to occur
Yeah, I have a HTPC, connected to a 32" LCD TV, that I use to listen to internet radio. I just have it sitting at the Windows 7 desktop, with a web browser open.
The desktop icons have probably been burning in for months, if not years. (Not continuously, but cumulatively.)
I initially thought that the vertical column of blocks on the left part of the TV, was because the movers shoved the TV next to my dining room table legs.
But after I switched inputs, to test another Windows 7 PC, and I could actually read the text under the icons burned-in to the screen, was when I realized that it was really burn-in.
It sucks. Now I'm thinking of replacing it. It works fine other than the burn-in, and is a pretty nice TV in general. Plus, it has not one but two S-Video inputs, which is a rarity on modern LCDs.