I did the same thing in London as well, there I even photographed some street scenes
I have shot many street scenes in London, and never had any sort of problem, ever. There are the occasional stories that over zealous security and occasionally a misguided policeman does sometimes try and prevent photography, but the chief of the police media advisory group has made it clear in public memos, that photography is unrestricted in public places. http://tinyurl.com/d6xmucn