Just what I'd like to add is don't leave the interview dejected if you think it went badly. I thought mine went horribly and felt completely dismissed by the interviewers, however, I recieved high marks in the interview.. so it's hard to tell what they expect. Mine was very art orientated, as I had done an art portfolio course the year previously. One of the interviewers wasn't much interested in my portfolio, but I had a sketchbook of some of my own "architectural" studies, with some basic concept design with references to architects, and just some photocopies from architecture books, and cutouts from magazines. Just show that you're interested enough to put some effort into it.
And all I can say is if you're going to mention names of architects, be sure you can back up why you mention them and would recommend to everyone to avoid the likes of Gehry in an interview, as you might get a bit heckled if you admire his work. And same goes for buildings, have a valid researched opinion on them, not just "it doesn't look great". Another thing I would suggest is investing in D.K. Ching's "Architecture: Form, Space, & Order". It's a book you're going to have to get in first year anyway, but it will open your eyes more to how an architect see's architecture compared to a layman.
Best of luck to anyone going for the interview!