Thanks, I understand that Kindle is a different standard. I have a Kindle reader app on my iPad, but not an actual Kindle app, so I'm wondering: does the Kindle allow authors to control fonts?
Every book I've purchased on the Kindle shows up in exactly the same font, and likewise for any documents that I email to my Kindle. If the Kindle hardware supports multiple font faces (aside from italic or bold face variants), I haven't seen any evidence of it.
Fortunately for me, I like the Kindle's font, so I don't consider it an issue for the type of reading for which I use the device.
Basically, Apple is doing exactly what Microsoft did with their early versions of IE6, where they rendered web pages differently than the others out there. They're ignoring a tag that's part of a standard because they think it looks better.
It isn't like you can say font=comic sans in an ePub book and expect it to take effect. What they're doing though is disallowing the setting of font families for certain types of tags.
Mobipocket (what kindle has) is a different standard. Amazon is mobipocket compliant.