An eagle-eyed MacRumors reader reported to them with a tip showing the above image. You can get that yourself right now, if you go to the iTunes app page and click where it tells you how many updates are available.
Basically, this seems to be taking an Android feature and adapting it to work with iOS. You should, theoretically, be able to set an app to update without you having to manually start it. That ensures that you receive the latest and greatest updates to whatever apps you enable it for. Definitely a useful feature, and hopefully one in a flood of new features that iOS will be enjoying with the impending update.