Looks like RHEL 6 is out.
Of course I’ve been using it for a while and it’s great.
This version has libguestfs-1.2.7-1.24.el6
(with backports) from back around April/May (when we started to stabilize and QA everything). Have fun using it, and when RHEL 6.1 ships it will come with libguestfs 1.6 which is much faster and more full-featured.