As has been reported in many places, there is a huge number of special events happening in the City this weekend. Traffic will be a challenge and parking will be even more of a nightmare than usual!
Muni and Golden Gate Transit will be operating extra bus service to handle the crowds. Although GGT is more expensive than Muni, this may be a good weekend to use it instead of Muni to get around. (The extra $2 seem to keep the crowds away!)
GGT special service: goldengate.org/news/…bus
Good luck! I'll be sure to stay in the East Bay this weekend. :)