Some time ago I was asked to do a study of our most popular open source projects to assess 1) what governance models are out there and 2) if the governance model has any effect on the project's success (such as size of developer community) on the one hand and on the other hand on the business of the related vendor(s). Some of the results are quite remarkable and have general applicability, so I wanted to share them here:

(Small updates done on 2011-07-14. OpenJDK size clarified on 2012-05-21.)