Thought about my own profile, and the reasons why I want to become a doctor. Didn't memorize answers to questions - this probably helped since it was a closed-file interview and both interviewers seemed bent on keeping it casual (and keeping me off-balance, in a way).
What impressed you positively?
Not much - had previous familiarity with the school, so the best aspects (location, research facilities, etc.) were already known
What impressed you negatively?
Neutral-to-hostile attitude of the school toward financial aid and supporting student travel
What did you wish you had known ahead of time?
School's inflexibility toward taking time off and students travelling on electives - we're all human here; people have varying interests and needs.
What are your general comments?
Decent interview experience - my first interviewer was coming off the floor and seemed a bit stressed, but that's understandable. First interviewer asked straight interview questions, the second (med student) was much more of a conversation.
Advice to all applicants: DON'T just base your decision on "rankings" or a school's prestigiousness, unless you have absolutely nothing else on which to base your decision (in which case you might want to rethink your career choice). This school is top-notch, yet I talked to so many students who seemed to regret their decision to go there. It seemed like a lot were attending merely because of the school's reputation, and are now unhappy as a result.