the interview at ucsf is pretty laid back, just as you'll prolly read on sdn. the only thing that kinda threw me off was that they told us to arrive there at 8 in the morning but my first interview wasn't until 1. and i had to take different shuttles to both interviews so by the time i actually got to it i wasn't as enthusiastic as i was in the morning. the only advice i would give you is that since it's closed-file, make sure you know what you want to tell them that's not already in your file cuz once you start talking open-endedly it's easy to lose focus of the fact that it's an actual interview. otherwise, good luck, it's nothing to be stressed about!