Hi SMW,
I received the same message, mine was apparently mailed out December 19th....it might be a 50/50 shot, since Pitt sends out interview invites via snail mail, or it could be a "thanks, but no thanks" letter...who knows....good luck to you!
I just received my first interview invite, GWU, I'm an August MCAT'er who found out that AMCAS had NOT forwarded my scores to anyone....I had to call there a few dozen times to get them to send them out..what a weird year..