Looks like TFL are pretty non-committal about expanding the scheme according to this article with the "Cycling czar" Andrew Gilligan. [www.bikeradar.com
That said there's a slight glimmer of hope in that they are 'considering' expanding to 'parts of Southwark'. Fingers crossed.
"We’re not going to expand the scheme significantly further – we are going to have incremental expansion though, what I call oozing: we’re going to expand it to the Olympic Park next year for instance, and there are demands for us to expand it to parts of Southwark, which we’re considering. But on the whole we’re not going to have any major expansions because it costs quite a lot of money and we have a very good deal with Santander, which has significantly reduced the cost to the taxpayer – and I want to spend the cycling budget on infrastructure rather than on cycle hire."