Here is a blog post for Docker on the progress on the Open Container Format. One month ago, Docker, Inc. announced the creation of the Open Container Initiative*, under the supports of the Linux Foundation for the purpose of defining common specifications around container format and runtime. Docker donated both its base container format and runtime, runC, and Docker began working with maintainers of AppC to create a common set of specifications. There has been a lot of progress in the past month, to find out more please check it out here.
Also here is a picture showing of our own Andrew “Tianon” Page at the Open Container Project Working Session at Docker Contributor’s Summit.