other than control center, I would consider the "smart multitasking" to be a kool feature.
from apple's iOS page:
Because iOS 7 learns when you like to use your apps and can update your content before you launch them. So if you tend to check your favorite social app at 9:00 a.m. every day, your feed will be ready and waiting for you. Thats multitasking in iOS 7. It knows what you want to do before you do.
iOS schedules updates during power-efficient times. Like when your device is on and connected to Wi-Fi. So your battery isnt drained unnecessarily.
also considering this was a full revamp, i expect more kool features to come in 7.x once they get 7 to a stable state.
in Jony we trust