I/O isn't even over. There's surely more news to come in the coming days.
All of the good stuff is happening in the smaller conferences that are following the keynote.
Notifications:
They are getting privacy settings to make sure lockscreen notifications don't show sensitive notification information to any old person who picks up your phone.
They have them broken into groups. Where devs can specify if notifications should be public, private or secret. The difference between private and secret seems to be that a private notification lists on the home screen but without any detail. It just lets you know theres a notification to check once you unlock the phone. Secret notifications are silent and don't present themselves at all until the device is unlocked (assuming I'm recalling his description directly)
And then some tools to help the notifications sort themselves properly on the lockscreen so the important stuff rises to the top when you have more notifications than can fit on the screen.
And of course, user control over notifications and sounds priority and more through settings:
This is the type of shit I really wish they would detail more in the keynote. But I suppose granular info would just put everyone to sleep. They all just want to watch cheesy videos and collect free swag, lol.