San Francisco has lots of neighborhoods that attract OOTers.
Though the same spot attract in-towners too, as SF has a very
large transient population. And not just the hobo variety - lots
of folks live there for a year or two and move on
Valencia & 22nd is probably the latest up&coming locale.

San Jose has it's SOMA district, which was pretty much foobar'ed
by the redevelopment nazi's until they gave up and let the area 
develop on it's own. It'll still take 10 more years for the 3rd largest 
city in California to have any sort of real nightlife destination point
(other than driving to SF).

 - michael