Well, there's a spectrum where on one end they just paint a big "A5" on the package and hype it as their own. On the other end they completely architected ever

Well, there's a spectrum where on one end they just paint a big "A5" on the package and hype it as their own. On the other end they completely architected everything on their own (which, clearly, they have not done). Somewhere in the middle there is the reality where they have not only made some power management tweaks, but have (according to the last keynote) added an Image Signal Processor that implements face detection, white balance, and image stabilization algorithms that are, presumably, not on the stock chips you mention.