I went to the SAIC sculpture interview in person last year, I had never been to Chicago, so that was fun.
For SAIC its an event. They started with an introduction in one big room with all the sculpture applicants who had been granted interviews. Again it was about 40-50 applicants to interview for about 12 or so spots.
You sit one on one with two of the sculpture professors. They ask you to go through the portfolio you submitted, which I did. Towards the end I showed them some current work I was making. They asked me to clarify particular parts of my statement, which I did. They didn't so much ask why grad school or why SAIC. The really just want to know about the work. They didn't asked curveball questions. ALWAYS have good questions for them. At the end, they will ask, "Do you have any questions for us", and you should have 2 or 3 questions to ask. My interview went well, I asked good questions and I think thats why I was accepted.
It wasn't particularly unique in any way, just don't be nervous, and just talk.