Well, looks like I may have an answer as to why audio is broken on my Gateway M685 under OpenSuse 10.1. There is no kernel support. In looking at the file include/linux/pci_ids.h, there is no listing for the 82801G High Definition Audio Controller. I can find it at the Linux PCI Id Repository, and it has an ID of 27d8.
I know from some limited kernel driver work I did in the very recent past on Linux kernel 2.6.15 that if you don't have your PCI ID to search with while enumerating PCI devices, then your device won't get found and returned to you.
If this is indeed the case, then until support is added for the 82801G to the kernel, I'm screwed. And I can hear the Linux fanboyz screaching now, "Add it yourself! You've got the source!" Lovely.