at the ucsd interview the dean of admissions said that people are accepted to both schools each year. he indicated that they lose a few to ucsf and vice versa.
UCSF. No doubt. San Francisco is home, my family and friends are there, and it is the #1 program in the nation. UCSD was interesting. I liked the strong clinical focus of the curriculum and the fact that it is new so they are open to letting you explore new paths. But for me staying close to home outweighs that. I doubt you can go wrong with either one though.