I just noticed while watching a standard definition program that the black bar on the left was wider than the black bar on the right. It's possible this is a new problem with .50, but it's also possible I haven't noticed before since I don't watch much SD.
Red October Standard does not exhibit this problem. WMC does not exhibit this problem.
I'm not sure if the problem affects HD programs (it could be that there is sufficient overscan in the signal that it still takes up the whole screen when shifted right). The other night I noticed that HD football had a small horizontal black bar at the top, like the whole screen was shifted down, but that might have been NBC's fault - I forget the details and I forget if I checked it against WMC or not.
This may or may not be related to the issue I've always had where SD programs show noise at the top edge of the picture when using RO HQ even when I have the "Crop edges to remove visual noise" box checked.
This happens on two separate computers (one NVidia, one AMD).