To my knowledge, Apple has never warned Mac developers against assuming their code will be running on a big-endian architecture; switching to the little-endian x86 would be extremely irritating for any developer with a code base that makes assumptions about byte order. Sure, most Mac software probably doesn’t need to deal with byte order directly; but for those apps that do, there will be significant drudgery involved.
/me looks at fPic code…
Oops… Damn you Mr Gruber. I didn’t need to realize *that* on a Sunday!