According to a post on the Facebook developer blog, the major changes are:
- Updated FBSession to receive permissions granted to your application at the time of login without requiring a permissions refresh. This enables your app to more reliably detect the current permission state of your app. This applies for any login flow except the iOS 6+ integrated authentication.
- Ability to set the selection property of the FBFriendPickerViewController that makes it easy to pre-select friends.
- Ability to set the login behavior for the FBLoginView control.
Facebook added that a complete list of updates is available in its change log.
iOS developers: Have you downloaded iOS SDK 3.10 yet?