" http://geetduggal.wordpress.com/2010/11/25/speed-up-your-pyt.... lists an example where PyPy is in fact faster than C++ with STL. Not sure how it would compare to well-optimized C, but remember that JIT warmup time will hurt you for short lived jobs."

But note a little further down the page. In the hands of a C++ coder (or indeed Cython coder) things look very different.