I\'ve just updated my Mac OS to 10.9 and I discovered that some (all?) of my Python modules are not here anymore, especially the Image one.
So I try to execute
Found the solution ... You've to symlink X11 like this ln -s /opt/X11/include/X11 /usr/local/include/X11 and then sudo pip install pil should work.
ln -s /opt/X11/include/X11 /usr/local/include/X11
sudo pip install pil