If you're a member of the BlackBerry Beta Zone and are fortunate to get BBM Beta builds via the Beta Zone, then you should check your Beta Zone app on your phone because a new Beta Build for BBM is awaiting you.
There isn't log of what is new with the changes but from a quick hands on, you can now add multiple files and/or images to your BBM contacts in conversation at once. Also, you have the ability to add stickers in group chats.
Yeah, that won't get annoying.. /sarcasm.
If you're not a member of the BlackBerry Beta Zone, you can sign up for it here and download the Beta Zone app here.