BTW: I am happy to be convinced about systemd advantages:-) I also would like to know how it fits in containers, e.g. if you run them for hosting.
FWIW, the first time I had to care about it was a few days ago when I upgraded one of my mythtv clients and it didn't start mythtv automatically anymore (well... it didn't start X anymore). It seems systemd just ignores whatever is in inittab, which is where I had put my xinit or startx or whatever it was. It was clunky and never felt really clean but it seemed to work. Originally I had wanted to set it up with a gdm autologin but autologin was broken. A bit of googling and there were plenty of examples of how to do it in systemd, and it seems so much nicer. Turn on box and mythtv starts, without having to fake a login or anything. Other than that, I haven't had to care. James