I found this site called VSChart which is a "comparison wiki". It is kind of cool, offers comparisons between any 2 things, and sure enough C5 is compared there alongside dozens of other CMS/Frameworks.

Here is the comparison to Drupal, and the links on the right side of their page will give you comparisons to other systems:

http://vschart.com/compare/concrete5/vs/drupal...

It might be good to update some of the features listed for C5, because some have questions marks indicating "not sure" if a certain features exists. It works like a Wiki, looks like anyone can update it... not sure how they fact check to make sure things are accurate.