> Which won't allow you to install certain core pieces of Debian software which have decided to rely on systemd.

Debian is committed to support sysvinit for the next release at least. I really doubt anyone in Debian will add dependencies on systemd "just because": if they do so they may have compelling reasons (eg. ConsoleKit is unmaintained and broken) and the correct reaction would be to fix the issue (eg. like the ConsoleKit2 people are trying to do) rather than forking Debian just to ignore the issue.

Not that forking Debian is bad and people should not do it for whatever irrational reason if they want: it's just that in this case there's no rational reason the same task couldn't have been carried over in Debian itself other than the fact that in your own fork you may accept lower quality contributions more easily.