I noticed that when I have PTP selected on my D50, that when the camera is attached to my mac, it doesn't display the "PC" on the top LCD. When I use Mass Storage, it does appear. I'm not sure if this is what it should do, but I could swear that it once said PC. Could anyone check with their D50 (just attach it to a computer using the PTP [which is what you should use anyway] and tell me if it says 'PC' on the top LCD) Nikon's support didn't know, and they want me to send it in, but if it's doing something funky, it's likely firmware and not hardware. Thanks!