The storage space for all the on-line books is really organized - each book has a label and a specific place. She told me a bit about everything, but also made sure to point out that anything she told me could very well change before I started to work there.
All-in-all, between the tour and the interview itself, and all the chit-chat, I was there for over an hour. That's a good sign for an interview, right? The longer the better - if they aren't considering hiring you they get rid of you quickly rather than waste time.