We have seen several performance improvements introduced on every merge window just after a new Linux Kernel is being released to the public by Linus Torvalds. This trends will always an interesting (and sometimes controversial) topics whenever new ideas came out since performance itself in most cases cannot be achieved without taking some risk and probably could break others as well. In short, gaining performance requires some sacrifices before you get the optimum results.
A new patch is being developed at this moment and it's predicted to be pushed to the main repository when Linux Kernel 3.1 gets released and a new merge window for Linux Kernel 3.2 is open for public. Phoronix already posted about this news. Follow the discussion on LKML