Cocoon compared with other technologies
Note: XMLForms is deprecated, CForms is the way to go. A new comparison would be fine and needed.
Zope and Cocoon: A Comparative Review - Written by Zope "partisans" but they raise good points. Note: Comparison is done between a Web Publishing Framework integrated with CMS (Zope) and a Web Publishing Framework "only" (Cocoon), so a bit unfair. Here some comments by Cocoon users:
SimilarServers: Other XML/XSLT publishing servers that we know of