“I can find no documentation of the iTunes music library format. It’s mentioned in a KB article, yes, but only alongside other iLife applications. It’s a way for Apple to decouple their iLife apps and have, say, iPhoto play music while doing slideshows.
He’s really saying ‘don’t use this unsupported made-up API, use THIS unsupported made-up API that happens to have been more reliable in the past’. But presenting it like it’s the Proper Way of doing things is deceptive.”
Tom’s right. That XML file – like many of Apple’s file formats – is undocumented. Sure, you can work out what it means, but there’s absolutely no guarantee that Apple will not move to another approach in the future, rip up that file, and do something entirely different.
Craig should remember that just because something can be reverse engineered doesn’t mean it is open.
Of course, none of this means Apple is against being open. It just means that it’s not a priority for the company.