It’s been a long time coming but I’ve finally managed to get native Avahi support implemented in CUPS. This means that CUPS will now advertise its printers using Bonjour. The CUPS dnssd backend can also discover Bonjour print queues. At the moment it isn’t automatically discovered by CUPS, but I hope to get that part done once this work is accepted upstream.
The package with this patch is cups-1.4.5-9.fc15.