Drupal 8 overview

Drupal 8 beta release is approaching soon. It is estimated winter 2013.
Drupal 8 will bring a major change in Drupal and even CMS community is that it will adopts many components from the Symfony framework.

http://www.duoconsulting.com/blog/drupal-8-developer%27s-view

So in Drupal 8, you can easily use Symfony to build custom modules, and use Composer to manage components like rails Gem bundle.

So if you are a Drupal developer, start to learn Symfony right now. If you learn Symfony, you will find its core idea is inherited from Django.

Anyway, Drupal 8 + Symfony will be very powerful.