When we went out to watch the Reds in SF last year, we actually stayed in Downtown Oakland....yes downtown Oakland.
Now my mental picture of Oakland before the trip was probably what everyones is...pretty darn scary.
But it was actually pretty cool....very diverse, clean, had some cool eateries and pubs and never felt unsafe even late at night.
I was very surprised...as was my girlfriend who was 100% against the idea to start with.
And it was great that we could take a nice walk about 8-10 blocks down to Jack London Square and take the ferry straight to AT&T or any of the major SF tourist spots. And could hop on the train and 10 minutes be in Berkeley.
As Iam a stadium junkie (25 of 30 off the list) We did go out to the Coliseum our last day to see the A's play the Sox.
And that was the scariest thing about the whole trip was actually the train station were you get off to go the Coliseum.....that place was like "Escape From New York" and "Night of the Living Dead".....at 1130 in the morning!
As to the Coliseum not much to see and do as has already been stated, but you cant get bored with the Bay Area as a whole...just a fantastic place, would move there tomorrow if I could afford it.