Mine is set to run automatically every nite at 3am. If the user is logged in, the patch will still run and have a message up asking them to reboot. If no one is logged in and the machine is on, it will run them and reboot on its own.
Admins on the machine, won't get the automatic fun, it sits in the systray and tells them they have updates. Our users by default have power user rights, not admins.
Ours is running via a group policy, thats how the settings are set and such..let me know if you need more info and I'll see what I can do.