Just a quick note on the easiest way I’ve found to install NumPy and SciPy on Snow Leopard. It can be quite a pain, since you have to leave the Apple python install alone, even though it includes NumPy by default. It does not support SciPy, and anyway it’s not the latest.
So, don’t try to build from SVN and all that fancy stuff. Just do:
1) Download the latest Python from python.org
2) Download the numpy dmg from sourceforge
3) Download the scipy dmg from sourceforge
Install in that order and move on.