I got asked a few times why I use Drupal for my sites, and have convinced one or two to try it out. But though I like the system a lot, many of its features I have used so much that I even forget it’s a _feature._ Thus I usually never mentioned the fine grain permission system, moderation system, how input filters are put together, path alias, flexinode, and the sorts.
If anyone would ask me today, I’ll happily point them to this article. “Why Xaneon Switched from Mambo to Drupal”:http://xaneon.com/content-management-systems/drupal-vs-mambo.html