Back in June this year after the WWDC, I posted an article on Apple's secrecy and how Tim Cook's new promise of doubling down on secrecy had seemingly worked. This is was an observation based on WWDC's iOS 7 announcement, where other than the fact that iOS 7 was going to look flatter, nothing had leaked out prior to the event. Fast forward a few months and almost everything about the Sep 10th iPhone event has leaked out. I mean unless Apple comes out with a totally surprising new product, almost 100% of what is going to be announced (from iPhone 5S to the lower chose iPhone 5C) on Sep 10th is already public information, thanks to multiple leaks and rumors. This is just the iPhone 5 event from last year repeated all over again.
So what has changed from the WWDC to now? The iOS 7 was designed in Cupertino and Apple has a 'god' like control on the Engineers working on its software, mainly in the US. However all the information leaks about the Sep 10th iPhone event is hardware related and since most of Apple's supply chain and manufacturing is abroad and outside Apple, it looks like they has very little control on the information leaks.
Remember the new Mac Pro teaser and announcement in WWDC. Other than the fact that a Mac Pro refresh was imminent (thanks to a Tim Cook's email), nothing was leaked out. Inspite of the Mac Pro being a hardware refresh, since it was designed entirely in house and is going to be manufactured in US, Apple again seems to be in full control of the information. Hence unless Apple starts its own manufacturing (in the US or abroad) and brings everything in house, with the levels of production of the iPhones and the other iOS devices, it is almost next to impossible to control these leaks. And however much Apple dislikes its surprises being spoilt, there isn't much they can do to control the information from leaking out from what seems to be mostly from their manufacturing partners in Asia.