Steve Jobs’ response on Section 3.3.1
It's funny, his main example of a "high quality cross platform app" was Mozilla Firefox. In my opinion, Mozilla Firefox is a prime example of why the intermediate layers (if Firefox uses one, I'm not sure) and the cross platform stuff is a bad idea. It uses its own weird certificate store instead of using the operating system's, its interface does not have a Cocoa feel in any sense of the term, etc.