Because of some other printing problems I'm having I did the following: -remove default printer (a usb connected HPC1350 for which a have a bw and a color queue, the bw queue is the default) -do NOT apply this -add exactly the same queue again make it default -apply Result: No <DefaultPrinter xxx> in /etc/cups/printers.conf, actually no entry at all for the added/removed queue in /etc/cups/printers.conf. lpq gives an error that there is no default printer.
What version of system-config-printer? Sounds like you aren't trying the re-written system-config-printer, and instead got the old one. Could you re-test please, and re-open this bug if you still see the problem?
Erm, I just fired up system-config-printer on my fully updated rawhide box (I wanted to test test1) and it looks like a full rewrite, is it relevant to retest this under this completly new version?