You won't want advice from someone who's lived here over 10 years, I've never even done the cable cars [:)]
As Neil said, there's a few threads, most still pretty up do date, many restaurant recommendations, mostly still valid and good, not worth adding to for the most part except to mention that if you feel tempted to go to the Cheesecake Factory at Macy's (a popular VF spot), skip it an go two floors down, they just opened Burger Bar - not even close...
Agree with HG, August can be downright cold on the western part of the city - at least by Cal standards - most days I'll see about four hours of sun at best that time of the year. We just had temperature in the 80s earlier in the week, though it's back to a more reasonable 60-something now. It's never too cold here by UK standards, but late Sept - early Oct are favorites if you want warmer weather. In the city, it's just almost never super warm either. Across the Berkeley hills, other issue, but then why would you want to go to Walnut Creek?
August does have the highest concentration of european visitors, then again May/June and fall are popular times for big conferences, so it's not like the place won't be busy anyway.
Ease of getting Gs varied historically - I'm not doing VS anymore but the Tue/Wed rule definitely applies here. There have been enough seats historically that getting upgrades close to date of departure has seldom been a problem, but reserving early has been harder. Recently, it was coming up much more easily, but that may change if business travel picks up. In the end, SFO flights seldom go out with a lot of J vacancies. The last time I saw more than a couple of empty seats was when we traveled on Dec 23rd a few years ago.
