Indeed, because it is happening in various different boroughs of London, the Met Police’s resources are stretched thin.
Main problem is it seems the rioters are using Facebook, Twitter and BlackBerry Messenger to coordinate their activities. Telling fellow rioters where to go next, and also using it to warn rioters in other locations if they spot the police are moving to their location.
I’m in the US, of course, and don’t know the London neighborhoods, but reports keep saying that the looters have moved through several more upscale neighborhoods and shopping areas.