Bit of a tangent, but I'm wondering if anyone here has had any luck with Cython? I'm starting to run into some performance bottlenecks with Python, and so I'm just now looking at Cython, PyPy, Psyco, and... gasp... C. From what little I've read, Cython is supposed to be as easy as adding some typing and modifying a few loops here and there, and you are in business.
I can narrow down performance in C/C++ quite quickly, but neither I nor anybody I know has done much of this for Python. Many people who I work with consider a Python implementation a prototype, while Fortran/C/C++ is mature real code worthy of attention.
The only real downside is that C/C++ requires a little knowledge of the POSIX/LINUX or Windows. This represents a learning curve, but when you are over it, it represents quite durable long lasting skills.