How can I log into the desktop environment as Root on a new mac running 10.6 or 10.7 without creating a user account? Under Mac OS 10.5, you could boot a fresh-out-of-the-box Mac into single user mode, mount /, set the root password, and touch .AppleSetupDone - this would allow you to log into the desktop environment as the root user without ever creating a 501 user. I've never been able to do this under 10.6 or 10.7, however. Has anyone been able to do this without first creating a traditional user account? 

Many thanks!
You can still use SUM by holding Cmd + S when booting up.  If I recall correctly from the last time I did it, that should automatically give you root.