I work in Oakland on a daily basis. I recently refused to perform an installation at a house in Oakland, because I judged the building to be unsafe to even be around, much less installing a satellite dish on.
I've seen some crazy stuff in Oakland, Richmond, and San Pablo. Hearing gunshots is so common that most people don't even look up at the sound. I've seen drivers driving around residential neighborhoods at 70+ MPH, taking turns "Bullet"/"Dukes Of Hazzard" style, as if they were involved in a police chase. I've seen brawls half a block away involving 20 guys, and I've seen brawls involving 3-4 girls. I've seen a drunk/stoned driver crash into a parked car, and I've seen a dude in nasty greasy boxers run outside to continue beating on his wife/girlfriend.
There have been a number of officers killed in Oakland this year, and there are definitely places you would NOT want to be after dark, I don't care WHO you are or WHAT you are carrying.
And, believe it or not, there are some very nice, exclusive, and VERY expensive parts of Oakland too.
-Troy