Compressing the tarball with xz instead of gzip would save about 5 MB, see http://thread.gmane.org/gmane.linux.redhat.fedora.devel/181336 and let me know if you'd like me to take care of this for devel.
I'm currently updating matplotlib to 1.3.0 and will use xz in rawhide then. The current build is blocked by bug #991342, but will close this bug now, as anything is now setup in git at least.