Well, I see nothing happening. The Terminal window remains on as the Desktop does. This is from the Terminal:
Mac-OS-X-Server-10-6-x:~ me$ # sudo nvram boot-args="-s"
Mac-OS-X-Server-10-6-x:~ me$ sudo nvram boot-args="-s"
Password:
Mac-OS-X-Server-10-6-x:~ memce_markernbsp;
And there it stays forever... No reboot at all. No single-user mode.