and to piggy back, I just had systemd go wonky on my system... Seems it decided not to talk to dbus. dbus was actually running. I couldn't login, issue a reboot command, start or stop processes. As I'm working remotely, I was kind of hosed. I kill'd -9 dbus, and that seems to have caused the system to reboot. I'm not sure though... there was no logging to investigate before OR after.
As has been mentioned, the idea of systemd seems like something to be looked at. Having poorly tested coded rammed into a critical part of systems is a very poor idea. The often espoused idea that if it's not rammed in it will never be sufficiently tested. That to me speaks of monumental arrogance and impatience at a minimum.