http://www.lmsnews.com/modules/content/index.php?id=15
Although the majority of the site appears to be in German, they do have 4 reviews on the open source course management systems Claroline 1.7.0, Interact 2.0, LON-CAPA 2.0.2 and StudIP. They seem highly anecdotal, but also honest about the ease (or lack of) installing and administering some of these tools. – SWL