It looks really nice. It would be great if you write more in specific on https://github.com/dotcloud/docker. So, what "size" can we expect, what kind of elements are part of the container. What "interpreters" currently exist for the portable format you describe. But also meta-level information such as the size of the team, why has been chosen for Go, and in what situations NOT to use docker. I've been following docker.io for a while for the purpose of cloud services for robotics, so I think I'm a nice example of a person who would liked to be convinced to use your solution. :-)