Note: 2.6.7 was released only for linux and only in the online yum repository (http://xcat.sourceforge.net/yum/xcat-core/). A tarball was not released for 2.6.7. The 2.6.8 release will be released for both linux and aix and for both online yum repository and the tarballs.
These are the changes since the xCAT 2.6.6 release.