Please, never ever seriously consider making pacman surprising in any way resembling to what has been unsuccessfully proposed. Does the pacman wiki suggest running the following line after updates yet?
find /etc /opt /usr /var -regextype egrep -regex '\*.pac(new|save)' A section describing the results of this might also hint to why you probably don't need to update your mirrorlist every time, why using rankmirrors is probably not a good idea and that critical stuff like ssh configuration should be dealt with immediately in the cloud, otherwise users might be locked out. Personally I also ongoingly ignore /etc/libvirt/qemu/networks/default.xml.pacnew because it depends on network device name. I think at some point I might have to discuss this with the respective package maintainer. Other than that, I don't like gentoo's way of dealing with this problems other than the fact they ship tooling to actually deal with the 3-way merge pacman expects from the user. I'd welcome suggestions on this and actually was not smart enough up to now to somehow have a script dig up the old version's unmodified configuration file (to be used in said merge). I know there's the pacman cache, but pacman itself doesn't seem to need that to know there's a merge going on. There's definitely potential in doing this that might benefit everyone, please approach me for a follow-up. cheers! mar77i