From what I could tell, the interviewers had not just read my entire application but they were very familiar with it. One interviewer had maybe five or six individual words written down on a piece of paper and that was it, yet he commented in relative detail about my application. He also mentioned that he was certain I was academically qualified, and other people said they were told similar things, which suggests they definitely know your MCAT and GPA.
That said, it bears repeating: If you got an interview, you passed that part. Be relaxed and try to enjoy the experience. I had a pretty fun day, the faculty and students are beyond welcoming. If you show you have a personality, a genuine interest in the school, and potential to fit in well with your fellow students, they will probably accept you. That's what I heard from current students, and as far as I can tell they were right.