Just noticed today while doing some testing for kde-print-manager, that whenever I attempt to print from any Qt/KDE application, like arora konqueror okular there's a large delay of some minutes after clicking "print" for anything visible to happen. This may or may not be related to my testing adding ServerName=... to /etc/cups/client.conf and/or having a 'cups' and a local cups server available or not. (i've tried every combination I can think of so far, to no avail or help)
Confirmed this seems to be f18 specific, my few f17 boxes tested (with relatively close versions of both qt/cups as f18) seem unaffected. Also, tried disabling firewall just in case (which was a chore in itself, no thanks to firewalld), but no change.
Ugh, rogue bad printer starting with "A..." on our network was causing issues.