Earlier quoted context omitted.
If you go with homebrew and virtualenv to handle the installs for your python development, most of the problems disappear.
Good to know that it's getting better nowdays, still I would not exchange my trusty linux distro to osx ;-) How are things when you have to compile python extensions on your own?
When Lion came out, I had problems with some C extensions that expect gcc, but found llvm-gcc or clang instead, though that problem is coming up less frequently. I don't use many exotic extensions so YMMV.