A question to the OP or anyone that also had an faulty USB problem. What were the symptoms that lead you to believe that there was a bad USB port. Im asking because I may be in the same boat with my base line 15" i5 MBP. Today I was copying large Aperture libraries from one external USB drive to another that was connected via Fire Wire and had the process quit on me about 3 or more times. I got a message as if I just pulled the USB plug out during the copying process. Looks like I might be giving Apple a call as well.