These are based totally on everything I have read on public blogs and my own intuition:
* Skeumorphism, the idea that computer-based interfaces have to appear to have textures to simulate real-world items in order to teach people how to use the interface, is by all accounts dead. People no longer need their calendars, address books, game centers to look like something else in order to know how to use them. Look for stitching, felt, leather, and silly fonts to all disappear from iOS7.
* Likewise, look for a flatter look in icons, no borders or glossiness. New system font, perhaps the skinnier Helvetica Neue that’s appearing on the WWDC banners. Going out on a limb, it would not surprise me if there are customizable system fonts and colors.
* Changes to the Notification Center and lock screen to show more info to a person glancing at their iPhone.
* Rumors are circulating that Grokr, a third-party app that works in a similar fashion to Google Now, has been bought by Apple and will be added to iOS7 like Siri was. “Siri Next” will access your location, email, music, calendar and anticipate what info you will need at that moment (and hopefully the NSA won’t be listening).
* ‘iRadio’ looks like a done deal by all accounts. A Pandora-like streaming music service with audio iAds and the ability to buy songs right from iTunes and fast-forward to the next song.
* More tie-ins to other social media sites, like Vimeo and Flickr.
* It would not surprise me to see more deals between Yahoo! and Apple, based on the fact they have a common enemy in Google.
* An improvement to AirDrop to allow file-sharing between iPhones, iPads, and Macs. Possibly connected to a Dropbox-like service as part of iCloud. Also, other improvements and enhancements to iCloud.
* Major fixes for Maps and Messages.
* The addition of third-party streaming media apps to Apple TV. It’s not going to be completely opened up to developers, but a handful, say HBO, will be able to be added.