I discussed this with a colleague of mine earlier today. I completely understand why they moved away from Drupal, but I'm not sure that "why Django matters to us" is the right way of putting it (although Django definitely works wonders for sites like The Onion).

"Why [a mature web framework] is the best fit for The Onion" is a more appropriate way of saying it. I've wrestled with enough blog platforms like Wordpress, where the client wanted it to work like a generic CMS, to know that the "You can put lipstick on a pig […]" phrase is very much applicable to web development.

Use the right tool for the job, damnit. And The Onion did.