I'm thinking about building a website to have some kind of public facing content, but at the same time, I would like to be able to build modules and plugins without too much of a hassle. I'm looking at things like Wordpress, Joomla, and Drupal, but I'm wondering if anyone has personal experience in using and (more specifically) developing for these applications.
Personally, I'm looking for something in PHP, but if you know of one in another language, feel free to post it to help someone else who is looking for something similar in language X/Y/Z.