It has nothing to do with what Blizz WANTS Warden to do on the Mac... it is OS X that prevents Warden from working... this is a direct quote from wikipedia:
So it's as simple as playing WoW from a non-admin account on your mac. Warden won't have permission to view another application's memory.
Another quote (from PocketGnome Forums):
I don't know of anything that will sim OS X, but there are several hacks out there that will allow you to run it on your desktop if you have the correct hardware. Basically, when Apple made their machines, they coded the OS with predefined drivers for certain hardware (ex. Corssair memory)... so almost all Corssair memory will work on OS X. Try googling osx86 and see if you can't find the information you are looking for.
For those in the market for a new PC, I would suggest looking into
Psystar. They sell machines that come with OS X preinstalled for a FRACTION of what you would pay to get an equivalent Mac. I am NOT saying "gwaa... runz-and-buyz-them"... I have a MacBook Pro... I am saying "look into Psystar as an option".