OpenStack is definitely an open source software project complete with the challenges of open source development: it's organized into projects (e.g., Nova the compute project, Neutron the networking project) which have developers that are focused on developing for that project. Releases occur every six months which means that the feature set is ever changing and improving. This means that companies that publish distributions need to keep up with them and support published versions for a period of time.
The growth of OpenStack has been interesting to watch. The number of commits have increased 10000% between 2010 and 2015. While they seem to be plateau-ing, OpenStack is seeing more and more adoption, particularly in private clouds where about half of these clouds are OpenStack based. That's not to say there aren't other high level use-cases like distributed storage for CDN-like activities, multi-site clouds or public clouds (though, admittedly, the economics of building a public cloud can be prohibitive). The OpenStack Architecture Design Guide provides additional information on these use-cases.
Given all of the above, it's easy to see why OpenStack is viewed simply as open source software. But, what they neglect to consider is what it means to deploy OpenStack within the organization:
- Bimodal IT: Gartner and other IT analyst firms have been promoting a framework that differentiates between legacy IT and the new IT ("Mode 1" and "Mode 2" in Gartner's lexicon, respectively; the difference being that Mode 1 was primarily concerned with the stability and longevity of systems whereas Mode 2 is more concerned with agility and rapid iteration). OpenStack is a Mode 2 enabling tool: it helps organizations shift their IT operations to a more dynamic model and facilitates the adoption of DevOps and PaaS.
- Transformation: Adopting Cloud is not an easy undertaking. It takes much planning to deploy it, certainly from a project perspective, but also from a governance and management perspective. The ability to manage and administer the environment is not innate in IT ops teams that tend towards Mode 1 operations; rather they require a significant will and desire to change and adapt to Mode 2 operations. OpenStack catalyzes this transformation, making it easier to adopt DevOps philosophies and PaaS deployment projects.