There's not that much difference in popularity these days. Of projects listed by Freshmeat, Perl is used on 3784 and Python on 3286 ( http://freshmeat.net/browse/160/ ).
A few years ago, Perl had twice as many projects as Python; now it's almost even.
Let's be honest, there's much more Perl code in the wild than Python, and CPAN towers over any Python network. The knowledge base is far greater for Perl as well (there are books on the DBI alone).
The Python version of the CPAN is called ["PyPI"](http://pypi.python.org/pypi). It was formerly called the "Cheeseshop".
From the PyPI front page: "There are currently 5256 packages here." According to cpan.org, the CPAN is up to "14749 modules" -- dunno how many distributions that makes though.
A few years ago, Perl had twice as many projects as Python; now it's almost even.