Hmmm... no separate management network, no OOB management firmware, no ECC memory. It's not much of a general purpose blade. You're not going to run a farm of these without significant operational headaches.

But there is so much demand for OS X workers out there. People are doing it already

What are OS X workers used for? I can't picture OS X doing anything better than Linux in the server space.

You can install your own memory.

Sure, but the chipset and motherboard need to support ECC. You can't just add a DIMM with ECC and have it work.