We are working pretty close with the Debian kernel team, you can see some traces of that on either debian-kernel AT lists.debian.org or debian AT openvz.org mailing lists. Specifically, we work together to bring good quality OpenVZ kernel to Squeeze, and this was one of the main reasons for us to port to 2.6.32.
But yesterday we tried to search for
openvz linux-imageon packages.debian.org and it gave us no results for testing. I then emailed Max Attems (who maintains our kernels in Debian) and this is his response:
it should be there now, the switch to libata did uphold testing
transition of linux-2.6 for quite some time, so testing had an
outdated linux-2.6 for quite some while
Indeed, the kernel is now there. So yes, Squeeze will have OpenVZ kernel, and I guess it can also be used by people who switched to Ubuntu 10.4.