After switchin to systemd, the shutdown process in Arch Linux suddenly seemed to take very long. The console output stopped at Stopped target Remote File Systems. From this point on, it took almost 2min for the next line to appear.

The wiki hat some helpful information about debugging systemd shutdown problems. Basically, I added some debug options to /boot/grub/menu.lst. Afterwards, the next shutdown resulted in a log file that contained details about the started services. The culprit turned out to be acpid. Since systemd is capable of hibernation and suspending the computer, too, I decided to scrap acpid for the time being and remove it via pacman --remove acpid.

I have to admit that I did not look again into the issues with acpid. Especially for laptops, it is probably preferable to use acpid than a pure systemd. If I suddenly get acpid working again, I will post an update to this note.