We remain excited about Docker as it evolves from a tool to a complex platform of technologies. Development teams love Docker, as the Docker image format makes it easier to achieve parity between development and production, making for reliable deployments. It is a natural fit in a microservices-style application as a packaging mechanism for self-contained services. On the operational front, Docker support in monitoring tools (Sensu, Prometheus, cAdvisor, etc.), orchestration tools (Kubernetes, Marathon, etc.) and deployment-automation tools reflect the growing maturity of the platform and its readiness for production use. A word of caution, though: There is a prevalent view of Docker and Linux containers in general as being "lightweight virtualization," but we would not recommend using Docker as a secure process-isolation mechanism, though we are paying attention to the introduction of user namespaces and seccomp profiles in version 1.10 in this regard.
Since our last radar, Docker has hit 1.0 and has been declared production ready by the authors. During this same period we have seen an explosion of tools based on Docker. We now have PAAS solutions in the form of Deis, cluster management in CoreOS and Kubernetes, and Microsoft, Google, AWS and a host of smaller players are offering or will shortly offer Docker hosting. Microsoft is even looking to support Docker in their next version of Windows Server. Aside from all this change, Docker is being used in anger now by many people, for dev & test and for production loads. We fully expect to see a large pace of change in the Docker ecosystem over the next year, and strongly suggest you take a look at what Docker could offer your own organisation.