I've taken some time to add details to http://www.openstreetmap.org/
The good thing about this site is that you can add businesses and buildings, much more detailed than Google.
I've attempted to add all shops in Forest Hill over the last couple of days as well as many large buildings.
It would be great if others add details that they know in their own area. Other areas, such as Dulwich have much more detail, so we have some catching up to do, but adding details is very quick and easy to do.