Well I see a CoreOS employee saying that the spec should remain compatible with Docker until after 1.0. The image spec was not "donated" to OCI, various people

Well I see a CoreOS employee saying that the spec should remain compatible with Docker until after 1.0. The image spec was not "donated" to OCI, various people decided to make a spec for roughly what Docker was doing already, in order to formalise it, with an agreement to do a 1.0 quickly. It was not a standard to create an all new spec, at least initially. There are a lot of existing images out there, so incremental change and backward compatibility is important.