Chances are you may end up with a story like this: http://groups.google.com/group/comp.lang.python/browse_threa...
Albeit micro-benchmarks may indicate that Python is 100-200 times slower than C++, they may not be applicable to the real world. Python can be very efficient. And when combined with libraries like NumPy, beating it's performance with hand-crafted C++ is difficult.
Emperor has no clothes.