I sometimes have faint dark shadows on the bottom of my LCD right after waking my TiBook from sleep. The shadow does not go all the way across the bottom, there are two of them, located just inside both hinges. Within a few minutes, they seem to gradually disappear. They are very faint, in fact unless my desktop is white, they would be almost unnoticable.
Is this common for a two-year-old PB, or is it possibly a precursor to something serious on the horizon? Other than that, the LCD operates flawlessly... no dead pixels... excellent picture, etc.