Hooray, glad to hear you're so excited! UCSD interviews are typically very laid back, you know, "Tell me about yourself", "tell me about your research", stuff like that. I did get a couple ethical scenarios presented to me, but they weren't that tough; and it really seemed like the interviewer just wanted to hear my thought process. I certainly can't speak for what all the interviews are like, but they are overall NOT stressful.
I'm giving the free clinic tour on Monday the 26th =]
And riceman, I'm giving the lunch tour on the 9th! Can't wait to meet you two 🙂