TheAL says:

Very cool. Especially since Drupal is frapping awesome and just about the best CMS out there. @muskratboy’s claim that it isn’t flexible is 110% untrue and the opposite of Drupal’s whole purpose for existing. It’s a lego. You have to build onto it. No one said it would be easy.

I’ve been working with it since 2007. It’s so much easier to do complex things with it compared to WordPress or Joomla. And that’s right out of the box, too. My only complaint about this list is that A) Most ridiculously impressive Drupal sites were built by a huge team of developers, which doesn’t give much hope to the people using it as loners, and B) Most of those sites hacked the actual core of Drupal and built functionality around it in ways people who can’t do that won’t be able to do. Kind of a tease.