$ SystemStarter start PrintingServices
This was not working so I updated cups from 1.2.8 to 1.2.12 (see sourceforge cups site for the last dmg package available) and modified both /etc/hostconfig and /private/etc/hostconfig to ensure CUPS would start by removing the cups line.
Restarted and all was well again. The Printer Setup Utility auto detects my usb HP printer for the first time after just turning the thing on.
If you want to stop or restart the cupsd nicely you use:
$ SystemStarter stop PrintingServices $ SystemStarter restart PrintingServices