drahn checked in my pdisk changes for OpenBSD/ macppc. I updated the command to allow type modification for existing partitions, which is something that always annoyed me about pdisk. Now you don't actually have to blow away a partition and recreate the exact same thing with a different type, to install OpenBSD.
I started researching implementing sound support for the iBook2 on OpenBSD/macppc. It's going to require a couple components, which the Linux folks have already implemented: a) i2c support for controlling the mixer, and b) misc. bits of configuration to initialize the Tumbler hardware. The Linux guys use the existing DMA sound-support framework to work with Tumbler, so but I don't know how well that will work w/ OpenBSD.