Showing the systemd version during the boot-up was a new feature added in systemd 217.
To get rid of the message altogether, add this to your kernel command line:
rd.udev.log-priority=3
To get the message to show the correct version after every systemd update, regenerate the initramfs:
sudo mkinitcpio -p linux
And there are quite a few ways to get version of packages, besides octopi, there is pacman:
pacman -Q package_name to get the version of the installed package, make it pacman -Qi to get full package info
pacman -Sii package_name to get full info of any package in the repo, not just installed.
:)