As a distro that iterates very quickly, Sabayon has already gone up three version numbers since this time last year. While this may imply that there are only small updates each time, the release notes seem to imply that there are always some fairly major changes going on behind the scenes. This iteration there’s support for EFI/UEFI boot and secure boot, and only recently the package manager had an overhaul to become Rigo.
Sabayon comes in four initial flavours: GNOME; KDE; XFCE; and a much newer MATE iteration. Each of these are just for a default environment, and the others are of course easily accessible from the package manager, among many more. They even include Cinnamon in the mix. Installation uses anaconda, the Red Hat installer, albeit not the brand new version causing some problems with people in Fedora 18. This means that the process is fairly painless, although unlike some versions of anaconda, you set up a user account during the installation, and not afterwards. This is good on one level though, as installing takes a while for the distro to be copied to disc.
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Also: Sabayon 11 Xfce - Still no love for me