System operations people are a dying breed. As with so many other fields software is eating also the world of puppet masters as software developers are taking over not only development of software but also set up of execution environments. If up until recently, the job of a software developer ended when he or she pushed the code changes to GitHub or some other code repository, it seems the responsibility of a software developer is expanding further and now the job of a software developer is only finished when a new software container is pushed to Docker Hub.
Over the past decade git and GitHub have revolutionized how software is developed. Now, Docker is applying the same revision control principles to the world of execution environments. Enabled by the fact that all infrastructure software is now open source, Docker facilitates incremental construction of execution environments using revision control concepts well known to software developers such as commit, diff, pull, and push. The whole field is still in intense experimentation phase so I cannot yet report of the first hand experience with Docker at Zemanta as we don't yet use it for production deployment. But I would definitely advise you to at least try it out and to see first hand how much potential Docker has. Just like containers revolutionized international trade, Docker might completely change how software is deployed, run, and, ultimately, developed.