[pdftex] no support for Mac fonts?

[Troy Goodson]

I'm looking for a little understanding here: why doesn't pdfTeX (I 
use teTeX) support Macintosh fonts?

Is there information 'missing' from Mac font files?
Is there something proprietary about the format?
Or, is it just that no one has had the impetus to support them?

I confess ignorance on many issues related to fonts, so I usually 
stay away from the topic, but I just can't resist asking this 
question.