Grahund-
I'm near you in the San Fran area, my office is in Nob Hill but my home is in the East Bay (I needed somewhere to keep the motorhome, the 150 gallons of water, and the various other preparedness items, along with all my other junk!). So for me, getting trapped in the City has me thinking of a few responses-

1) I can hole up in my office until the smoke clears, if the building has survived. If it hasn't, I have a contingency plan for alternate housing and an evac plan as a worst case scenario. Think open water (hint).

2) I try to plan for every eventuality, but there is an inherent risk in being in SF from a population density perspective. That being said, who you know will make a difference in how you make out, as stated above.

Always cracks me up when someone responds to those of us living in California that we should "move"- I love this state, and the risk of calamity is everywhere.
When I lived in North Carolina, our house was ravaged by Hurricane Gloria. When I lived in Ohio, we had 96 hours of a below zero no power blizzard in '78. Hawaii- Iniki hit. Tucson-the Rillito overflowed it's banks, Mt. Lemmon burned up, and killer bees ate my dog. New Mexico- ice, fires, plague carrying Ebert's squirrels, avian flu carrying crows. And hot chile. Really hot chile. Danger lurks everywhere.

And so do geese- beware.