[arch-general] Btrfs snapshots for upgrade operations

Hello all, Firstly can a TU or developer few it to the dev mailing list, as I don't have access. Archlinux is supporting btrfs for root filesystem some time now. Have any work or thoughts been done for supporting snapshots before update packages? This way you can keep record of what's happening to your system and easily rollback if something breaks. I know Fedora and Suse (if not mistaken) supports that with their package managers. Of course I am talking about an optional feature enabled only from the user, not by default. Thoughts, ideas, discussion are welcome. Regards Leonidas