Since this thread is getting hits I'll just go ahead and re-post what I PM'd to the OP.
For a medical student a rotation at UCSF is largely a self-guided affair. You are not given a set schedule but are free to rotate with any attending you wish. Generally, most students rotate with a few faculty to see which one's they "click" with. Then, they focus on one or two specific people so that they can get letters.
Big/influential names in our department include Roach (Prostate), Wara/Sneed/Larson (CNS), Haas-Kogan (Peds), and Fowble (Breast).
If you have the time/motivation it is also possible to get involved in clinical/physics research. Just ask around and you should be able to find a project that suits you.
The residents here are very chill and the atmosphere is laid back. Just be yourself and prepare well to see your patients and you'll do fine. Enjoy weekends/holidays/nightlife in SF there's no other place like it!
ADDED: One of the interview impressions noted that faculty attendance at medical students talks was, at times, non-existent. Sadly, I have to concur. I would suggest working with one of the attendings here on your talk (even if you've already completed) both to generate interest and gain some feedback. One student who did this for her talk had the entire cadre of site-specific faculty show up.
