I can help with this as it was my friend's 2006 M3 that was keyed. Mark's M3 was the titanium grey one and is a beautiful car. He inspected it prior to the event and no damage was noted. We noticed the keying on Friday afternoon when leaving the Fontana Dam area for the pic event. The damage is about one foot in length, on the back rear quarter panel.
Mark is not in need of money and I have spoken with him about this thread. He's touched and a bit embarrassed with the attention this is getting.
What sucks for me is I convinced Mark to attend DGRRX, telling him how great the rotary community is and then this happens. He's still high on the people he met but for me, this does give us a bit of a black eye.