Changing how iOS handles notifications is one of the biggest reasons to jailbreak, at least in the pre-iOS 7 beta days. There are countless tweaks in Cydia for doing just that, and as many again that change the way the iOS lock screen looks and functions. It's arguable that the lock screen is the area of our iPhones that we see the most, so having it work just the way you like it can be of high importance to many - that's probably why there are so many tweaks, really.
The use of animations and transitions is possibly one of the least talked about, but possibly most obvious additions to iOS 7, and one of the first things you notice when testing the beta versions out having come from iOS 6. When used correctly, animations can make a smartphone feel alive, but when used incorrectly they can make it feel cheap and gimmicky.