Play with both.

Perl and python are very different languages. They're both good. You might find you're vastly more productive in python. I'm vastly more productive in Perl.

(declaration of bias: I'm a Catalyst core team member and would be delighted to see you on #catalyst on irc.perl.org :)

If you already know perl, then there's no reason not to use Catalyst. While it's lacking in the shiny marketing (build a blog in 5 minutes) that other frameworks seem to like, it's a good bit more flexible in terms of your choices of Models and Views, and in the way that you can present dispatch logic than other frameworks.