NOTE: Idealware came out with a revised edition of the report. See it here:

http://www.moiagroup.com/archives/comparing-cms-2010-edition/674

We just came across this fantastic new report from a company called Idealware which reviews open source software for non-profits. It looks at Plone, Drupal, WordPress and Joomla and presents the pros and cons of each in a non-partisam way. Recommended reading for anyone interested in CMS. They ask you to give your name and email, but this is a small price to pay for information of this quality:

Download the report now