I haven't spent any time playing around with Docker but experimented with
Vagrant plus Virtual Box.
You need to understand that Docker is NOT any container-solution similar to
OpenVZ, LXC, Jails, etc.
It's more like a layer between some container virtualisation or something
like Vagrant plus VBox and the outer world. It enables you to use the
virtualisation technology below to encapsulate your server / application.
Then you can upload your server / application to some "repository" and spawn
it everywhere (physical remote server, local host, clound).
Have a closer look here:
http://docs.docker.io/introduction/technology/#introduction
You can also use LXC for Docker as far as I understood from the few
presentations I have watched on youtube.
