I've just read the licence for the Hoefler font (see their EULA). It says explicitly:
You may not create Embedded Documents, except as expressly provided in paragraphs 3.2 and 3.3:
and "Embedded Documents" includes "ordinary" PDFs.
Now it may be that Apple has a different licence that is in force when I "bought" this font through Mac OS X. If so, where do I find it? (More generally, for any font distributed with Mac OS X.) I'd quite like to know that if I create a PDF with one of these fonts then I'm not breaking the law.