In a lot of iOS 7 icon redesigns, the designers keep each icon's detail small and centered in its respective tile. They're more gracious with the negative space. In my mind it feels like they're a little too frugal with the illustrations that give each icon its personality.
If only the icons in iOS7 were more carefully designed as with these. I have a feeling that changing your icons is going to be a more popular thing in iOS7 than in previous versions of the OS.