iOS 7 is the bigger change to iOS since the release of the original iPhone.  Not only does it have visual differences, but the underlying code has been completely revamped to add features like never before.  There are subtle differences in iOS 7 that many may not appreciate or even notice until you’ve used it for some time.  iOS 7 is a great update and despite the few visual queues I personally don’t like, it was worth the wait.