Now in its 10th year. Dancing in Golden Gate Park has never been so much fun. Come and swing dance under the sun. These days they're usually setup near the de Young on JFK (near the de Young Tower).
Nice set of reviews of various eateries at the Ferry Building over the course of several days. If you haven't eaten at the Ferry Building, this will get you itching to do so.
If you're commuting into the city (esp. over the Bay Bridge), you should know about casual carpooling. This site tells you all about the places where you can pick up riders or hitch a ride into town.
Looks like the vacant FAO Schwarz store on the corner of Stockton and O'Farrell is finally getting a long-term tenant in the form of a new Barneys location.