Here's the gist, though: Apple has built a complete, robust physics and particle engine for iOS 7. Elements don't just go from point A to point B, they move through a "real" world. They react to the accelerometer and gyroscope, they collide and bounce off each other and with the edges of the display, and they can change color according to the environment around them.
Many are considering iOS 7 just a re-skinning of Apple's mobile OS. I knew there had to be something else to this. Apple doesn't just do redesigns. They usually include a healthy amount of rethinking with their redesigns.
As a side note: Mr. Ritchie has been killing it for a while now over there on iMore. He's one of the few that really gets Apple. Which is saying a lot since that is not an easy thing to do. I wouldn't even put myself in the category.