The question is, by "optimized", do they mean just the UI of the app? The article mentions that the apps must be build with xcode5. But it doesn't specify against which iOS version it must be build.
Do they force devs to not just make their apps looks like iOS7 but also force them to use iOS7.x as a minimum build target? That would really suck considering there still are devices out there that are ineligible to upgrade to iOS7.