Re: Another "new" Apple innovation?
@AC OP, iOS already allows that stuff too, but currently applications need to ask for their own set of login credentials to Farcebook.
iOS6 will allow users to login to FB globally in the OS settings if they wish (presumably, like the Twitter integration, each app will still be able to do it individually if you would prefer).
This feature is not available in iOS5, so it fits the criteria for "new" in the context of the developer keynote where it was announced.
Each version of Android has features that are "new" to Android, but may have been seen on other platforms first, not every feature is truly innovative you know.
New doesn't have to mean "never available anywhere else, ever", you know.