Congrats! This was my best interview experience by far, and I am sure you will love it. The interviews themselves consist of 2 traditional 1-on-1 interviews with people affiliated with the school in some way (research/admissions/physicians/clergy etc...). They are open-file except they do NOT know your grades. However, my interviewer asked me about mine so I ended up telling him/her anyways. The interview group only consists of a few people (mine had 4 people total) so you will get a lot of personalized attention. They really make you feel like you aren't just "another applicant." You will also have a nice tour (they have a really nice gym nearby) and free lunch!
Personally, I read through some of the older school-specific threads for Loyola-- some of the med students leave really useful comments. I also read through SDN interview feedback and their website. They have a big emphasis on holistic care and treating the underserved. Be prepared to answer "Why Loyola." Good luck OP! Matt and Judy are both great. I personally did not meet the dean because of my interview times, but from what I heard she is awesome as well. Oh also, stay with a student host if you can, that really helped ease my nerves on interview day as well.