I normally try to stick to posting original content on my site, but I ran across this post today while doing some research for the Hacker High School project.
It presents a really well structured analysis of the communities that support and give life to the main Cloud Computing projects: OpenStack, CloudStack, Eucalyptus and OpenNebula. All the information was extracted from public forums and code management systems.
You can find the post here: http://t.co/qmwUUcsiHu