I came across this while looking at voice chat software:
http://www.ventrilo.com/overlay.php#vista
If they can/have found a fix or work-around for teh OSD issue on nVidia cards, then maybe they might share the idea? Couldn't hurt to ask anyway. If they do/can/will, then we can get herostats working in full screen again like it does on XP.
Should work with the new "Auto-adjust game client window" option!