Is Blackberry trying to turn it's Blackberry Messenger app into a social network? The Answer to that question would be a hard YES.
With the new update to the News Feed that allows BBM users to like the photos of their contacts in their News Feed, added to the already present ability to comment on those photos. One could argue that the guys at Blackberry see the BBM app as something that's a little bit more than just a messaging app.
Besides the like feature, the BBM update also brings the ability to retract sent photos, also retract all sent messages, retract and edit messages in a multi-person chat and group chat.