Yes, it is the result of the Share Leaderboard Update function inside the THREAD context.
But before the new SDK version, you could only see your score update. Now you may also view closest scores from your friends via a slideshow.
That is a really nice feature indeed, but it is actually not related to the new SDK. It has worked like that for a year, and there was no update of the updateAsync within the new release. (I know they have had some bugs with the leaderboards, so maybe something got corrected at the same time though so it now works like that for you... )
The new friend leaderboard function is not related to contexts (like threads etc)