I didn't really have that much down time; I arrived early and had 15-20 minutes to chit chat with other interviewers, and maybe 10 minutes waiting on the info session to start (although, I did take maybe 15 minutes to find my interview location immediately after getting my info packet). The assistant lead me to a small conference room while I waited for my interview time. My interviewer was already with one candidate, and I waited with the guy after me for maybe 5 minutes before I was called.
At last year's info session, one of the Co-Chairs said he spent the morning interviewing three candidates and would have three in the afternoon; I have no idea if it's the same for all of the interviewers or not.
Overall, the interview day seemed really relaxed. Jose Espada with Financial Aid is a great guy and he's pretty funny. The interview itself, for me anyway, was relaxed and conversational. My interviewers used the entire 45 minutes and were very friendly.