HI, Alaine. I'm from a suburb of San Diego. Most of us in Urban California cities are nervous about the roads and traveling on them, and that goes for the "experts" as well. I've lived in SD nearly all my life, and I certainly sympathize with the SF cyclists' situation. Our problems here are: DISTANCE, if you're in a suburb, lots of hills everywhere (great for fitness, but they do provide a challenge), problematic routing (How do I get to Escondido by bike from El Cajon without traveling a freeway, for example? Never mind that it's 40 miles one way, if I'm biking to work) and drivers who seem to regard bicyclists as targets.
On a positive note, there are lots of cyclists in urban areas here, but they don't seem to travel between them much. I'd be happy to answer the questions, but I've only been to SF twice, and my immediate memories are steep hills and narrow streets, and CROWDS.