For me one of the best ones is the fact that you will no longer need to enter your password to update apps, only to purchase them! I can't believe it has taken this long but I'm really glad to know this is finally going to change! I've always found it so annoying that I have to type the password when all I want to do is update an app. I mean, I know they are just trying to protect me, but updates are free!
The Bluetooth option will no longer be hidden in the General settings, it will now be right next to the Wi-Fi option. This is great news, I'd much rather have a widget type thing where I can easily turn it on and off from the home screen but this will do.
You will be able to set up specific notifications for specific people. . . wasn't this already in iOS?
Finally and I can't believe this is new either, there will be a CLOCK application with a stop watch and a timer and an Alarm!
Nothing extremely exciting but a lot of times these tiny changes make the biggest difference. Making things easier on people is always a welcome addition to any OS.