LSS: Secure Linux containers

True yes, but in many ways it is a good thing. namespaces are really useful for all sorts of things (eg testing networking code) that is not a full container. The jail-style just have a container model is much less flexible as it makes assumptions as to how you work. There are only 2 major projects so far (even if confusingly named), so most people find one or the other I think. The issues are more to do with documentation and bugginess particularly if eg you dont run lxc on up to date Ubuntu but try to run it say on Debian, which is not well supported yet due to versions.

I suspect most serious users (ie not just running for testing and so on) will probably have to dive in and customise the setup to run the kind of container they want, depending on what they want to share, as clearly one policy does not fit all.