Quote:

is, is and is. Now read that:

Dev 1:

1) Open Firmware compatible PCI Express Radeons are in short supply. Without a such, you'd have no access to the firmware, which makes installing and using the machine quite a hassle. Reflashed cards are not a solution either, as those cards tend to be misconfigured by the flashed firmware, leading to all sorts of trouble on the OS side.
2) A lot of hardware is different from previous generations of Macs, and thus require completely different code to support. Ethernet and the cooling system are two things, but there's also things like processor frequency and voltage control, which also has to be handled by the OS. There are other things to deal with as well, and those would then have to be tested and adjusted for each revision of that Mac.
3) PowerMac11s aren't so much better than the PowerMac7s to make up for the required effort

Dev 2:

There are still missing drivers including fan/cooling management. There is no onboard eth support and there are already way too many configurations we need to support.
Late 2005 G5 PowerMacs also came with nvidia cards by default mostly which are not supported as well and require anyone interested in MorphOS to get a supported graphics card first which is not that easy to aquire if you still need OS X/OF working.
I'm sure there a few people who don't really care about this issues and would still like to run MorphOS on such machine - even one in our team does - but this most likely doesn't account for a reasonable amount of users.

As you can see both devs are stressing the gfx card issue (which is not such an issue for us, users, but who cares?). Who's right? Koszer's right! :)