The OpenSolaris project is an open source project which was initially based on the source code for the Solaris operating system. It is a community development effort, providing a forum to collaborate and improve operating system technology. The community has grown from its original roots in Sun Microsystems to be part of a much wider community, incorporating a wider set of interests and ideas, to where it is today, a diverse community of people from many different backgrounds, right across the world contributing to the project.
The governance constitution details the OpenSolaris community organizational structure as a whole, http://www.opensolaris.org/os/community/cab/governance/, loosely described as a set of community groups growing up around a set of projects and technologies, each formed by various participants, contributors and core contributors (or members), working under the guidance of the OpenSolaris Governing Board.
The community has well over 20,000 officially registered participants, spread over 40+ community groups, and 50+ user groups worldwide. OpenSolaris also has several distributions derived from the base operating system, including Nexenta, Belenix, and Solaris Express. The number of people contributing code is still relatively small due to some infrastructural barriers in moving the source code management system out behind Sun walls. We have made significant progress in this over the last year, and the beta program for a fully read/write Mercurial repository available is nearing the end.