Evaluation framework for Open Source CMS

The above title is the subject of the master thesis which I am writing currently. In little more than a month I will need to present a complete paper for judging. Since I am working fulltime during weekdays it leaves evenings and weekends for this fun activity. Tired? Yes. Interesting? Yes. It was when I came in contact with Drupal last year which I began to see the potential of CMS's. Now I am also looking at Joomla and Wordpress and trying to learn as much as I can. By drawing on the experiences of others and the theories of CMS and usability I hope to come up with a framework which can be used when choosing between different Open Source Web-based CMS's.

Studying requires a lot of books