Hm... looks like no one ever got back to you:

> I am interested in installing NetBSD on my PCI MAC in place of mklinux. 
> However, I do not want to lose the MacOS.  LinuxPPC has bootx, and mklinux has
> a dual boot. I have a dual boot on my i386 PC between NetBSD and Windows.
> Where can I find info on booting between MacOS and NetBSD? Does such exist?

At the moment, you can't: you'd need to have two disks, one with
NetBSD, and one with MacOS. People are working on getting
NetBSD/macppc to read Mac partition tables though, so you will be able
to do this at some point.

-- Dan