I had F15 with cups-1.4.8-5.fc15. I upgraded to F16 beta with yum distro-sync and ended up with cups-1.5.0-14.fc16. When I rebooted, cups wasn't started. Since it was configured to start on boot in F15, that should have been preserved when I upgraded to F16.
Use systemd-sysv-convert to do this. https://fedoraproject.org/wiki/Packaging:ScriptletSnippets#Systemd