I have enabled OSS, no-OSS and UPDATE with priority 99 (default).
I have packman repositories with priorty 50
And openoffice with priority 70.
But when i use autoupdate (either yast–>on line update or zypper update) packages from those repositories are not selected as default and I have to manually update each package.
You could use this on other repo’s Eg: kde4 Build Service repo’s. if you have them. But they are not necessary really. And I would advise using this really just with Packman to ensure all Multi-media is from there.
Otherwise updating is easy. I don’t use the updater applet though. Just software management.