Other features Windows Phone Central can exclusively reveal that are either coming to Windows Phone 8.1 or that are actively being worked on including micro SD card support for installing apps and games. This feature is especially important for low-cost devices, like the Lumia 520, where internal storage is limited to just 8 GB (and less than 5 GB actually available).
In terms of the notification center, we can reveal that they work even on the Lockscreen. The Lockscreen can still be swiped up like normal to unlock the phone, but in Windows Phone 8.1 you can also swipe down to go directly to the new Notification Center.
The default camera app is also being updated, with buttons and functions similar to the Windows 8.1 camera app, though these will be located on the left side of the viewfinder.
First-party Tiles, like Email, can be swiped towards the left to clear the Live Tile of notifications/counts. Currently, users can swipe to the Right to bring up the full app list for the OS, but swiping left will clear any Tiles without the user having to open the program directly in 8.1. As of now, this feature is only open to first-party functions like Email and the People Hub, though presumably Microsoft could open it up to developers via an API.