There is a huge number of articles that review Drupal and Joomla! - two the most popular CMS's (Content Management Systems). Most of them are very interesting, educating and entertaining. But until you try it yourself it's useless.
For a new site Mobile Polyglot I decided to try Joomla! first and spent about nightly 4 hours of trying to create a simple, not to say, primitive site. After 4 hours - there are still problems on how to do this, how to change that.
Drupal - 1.5 hours and everything is done! Very elegant and intuitive. Surely, my needs were very primitive and there are a lot of other tasks are waiting in the future. But for the starters - Drupal is the best!
And check out Mobile Polyglot!