Tagging users
Application can tag people in updates. Permissions needed.
The application can add a personal message to the update and also add it after the action was published.

User generated photos
It is now possible to post large photos in the news feed even without uploading it to a Facebook album.
The difference is that the image is uploaded to your own server. The image URL is then passed to the Open Graph together with other optional values like:
sources – Image URL
large – If the image should be big (boolean)
expires_in – How long the post should exist (seconds)
tags – User ids in array to pass tagged users
message – Your personal message
place – Id of Facebook place
your own actions – Verbs

Post it to the graph with /me/[namespace_of_app]:your_action

Download the example application here: https://bitbucket.org/brucehazan/ios-sample-og
Example includes single sign in with Facebook iOS SDK.

Add app from Timeline
If friends are using a Facebook app and a post appears in your news feed and you don’t have the app, you can install the app in a click of a button. The button on the post says “Add app”.
To enable it put a URL in Profile URL in application settings.

Publish past on user timeline
Post past things on the users timeline
Button to fill out past timeline

Map Stories
Specify long and lat on a page can be added in meta tags. Your post can be associated with a location.

New Feed Aggregations
The more traffic a post gets it gets highlighted in the news feed.

Action links on OG Stories
Accept Diff – Authenticate the application to display application-functionality in the post:

offline_access – Depreciated
Valid for 60 days is the only thing that can be used. As long as the user used your app you have 60 days to access the user.

publish_stream includes publish_actions by default now.

iOS Deep Linking
It is possible to deep link into an iOS app from posts of the mobile Facebook app. If the user doesn’t have the app, the user will be directed to the App Store. After installing it the deep link is active.
This is not new but it just launched for Android.
To enabled it just check the box of iOS Native Deeplinking in your Application settings.

Facebook requests
Facebook requests from Facebook applications can be sent directly to the iOS device linking the user directly to your native iOS app with Facebook integration.

App Center
Facebook launched the App Center where all Facebook apps are shown in an App Store-like matter. The apps will show screenshots and rating from users.