Brent and Lewisham were the first two London Boroughs to seriously tackle their library strategy as the Tory/Lib Dem cuts began to bite. The two took very different approaches, with Lewisham going for a volunteer or community based model. I suggested before that Lewisham seemed not to have had the success that they may have hoped. Nonetheless, they seem to be extending the volunteer model to more branches. This is a fairly controversial route.
Brent's more old fashioned approach of maintaining staffed, extended libraries at fewer locations seems to have resulted in higher user satisfaction and better performance in terms of key metrics.