It will continue to rise. It will be less than it was since it rebounded from the credit crunch but it will still continue at a fair pace. This will be driven by high amounts of immigration and further shortfall in the number of properties being built.
Yeah, it'll go up long-term. London is, and will remain, a desirable place to live. It would be naive to think London is somehow immune from bumps along the road though. It's vulnerable to falling consumer confidence and the credit markets, just like everywhere else.