I realize this is the G10 thread, but I recently purchased an S1, and while I was watching the latest Harry Potter movie, the brightness/luminance of the set seemed to suddenly "jump." Now, I don't think I'm losing my mind here, as the black bars seemed to suddenly become brighter during the movie..
To note, I didn't "break-in" my set, and this occurred around the 100hr mark. Perhaps the firmware has preset points where it raises the brightness/luminance of the set? Perhaps during the "break-in" period Panasonic keeps the display a little dimmer to prevent burn in? I'm not sure what the reason is, but the display most certainly appears to be a little brighter now. Hopefully it doesn't get any brighter.. Just wanted to report that perhaps this is happening on many panasonic displays..?