First, there are several battles over the tearing down of old buildings to be replaced by condos. Among the buildings being fought over is an abandoned cottage, an old abandoned theater, and an old abandoned church. The cottage is old and small, the theater hasn't been used in years, and the Catholic Church abandoned the church years ago because of a lack of parishioners. On the other hand, the buildings are old, uniquely designed, possibly historic, and in the case of the church, kind of cool inside. Right now, each building is set to be torn down but local activists have fought the building's destruction by claiming they're landmarks. Does something old make something worthy of keeping even if nobody seems to want it? As the Examiner points out, a process for how city designates landmarks doesn't really exist. Luckily, solutions on what to do in these kind of situations are out there as John King of the Chron has pointed out.
Artist rendering of Rincon Hill Project from SFGate