I'm a drupal evangelist 99% of the time, but their releases are all over the place and the taxonomy system can be a little more than taxing at times. What I do love about drupal is that it allows the use of php in both the templates as well as any content you create. Before drupal I was a die-hard XOOPS user, but it's just too damn heavy. I used Mambo before it was Joomla and found it more counter-intuitive than intuitive. Any ideas?