The intent of the benchmark was to show benefits of LXC as a technology in the Cloudy space. It just so happened I chose docker as the LXC "provider" for these tests -- it could have just as easily been libvirt-lxc or something else.
Given OpenVZ is an LXC technology, comparing docker to OpenVZ would have been more of a comparison between different LXC providers. I agree this would be interesting, however not in line with the intent of the tests.. BTW -- I'm aware that OpenVZ is probably the most mature LXC solution out there.
As for docker vs Xen paravirt, that would be interesting as well and the information I presented clearly stated additional testing is warranted. I would encourage others to try such configurations and present results.