We're certainly still evaluating alternatives, here.
Debian is much closer to what we use internally, and we wanted to start with sharing some of the internal ways we work.
LMCTFY is a "container" implementation by Google's traditional definition, which is very focused on isolation and less so on namespacing, filesystem, and packaging. We've added namespace support recently, but we do not have the things that make Docker really interesting to most people - the build process, the packaging, the runtime.
LMCTFY is just a piece of what Docker does. They can be made to work together, even.