First chapter of "Discovering house music in San Francisco" is written by Carl Cox last Saturday at Mezzanine SF. He plays once a month in New York's best house/trip hop club Cielo but running into him in San Francisco was unexpected. His set got better and better since the last time I saw him at Ultra Music Festival.
Mezzanine is a nice venue-concert hall but definitely not a high-end night club. However, Simian Mobile Disco is going to be playing there at the end of this month, so tickets already bought for the second round.