In this talk we explain how the open cloud computing industry ecosystem is evolving. This is not a talk about technology but about the forces that shape the cloud computing industry. We show how after becoming a rival to proprietary software in all segment of enterprise computing, open source software in now driving innovation in cloud computing. We explain the specific nature of open source in cloud computing and we evaluate its strengths and limitations. In this context, we position and analyze the strategies and probable evolutions of the main open source communities that constitute the open cloud ecosystem. While new technologies are quickly becoming mature on the cloud execution layer (or IaaS) front thanks to communities such as OpenStack and Apache, everything remains to be done on the upper layers (or PaaS) of the cloud-oriented information system.