Firstly, Jo Brand is only partially right. Streatham is like South London's answer to Dalston. It is quite near Wandsworth, Clapham and Balam (like Dalston is near Islington and Clerkenwell) - neither area compare particularly well with their neighbours.
You live in Streatham when you can't afford Clapham.
I wouldn't live there, but I wouldn't exactly call it a ****hole (it has some lovely Victorian houses - but rubbish transport links).
Also, Jo Brand is a national treasure. Her last comedy ('Getting On') is one of the best sitcoms of the past ten years, and let's not forget, it was Jo Brand who spoke up against Carol Thatcher calling Jo-Wifried Tsiona a g*llywog.
For these two things alone, I think we should cut Ms Brand some slack.