The industry is actually betting you'll move to Joyn over another platform once it starts being installed on all phones (Q3) in europe but i have my reservations on this.
BBM crypto is actually compromised in a few countries (UAE, India etc...) RIM gave them the key to allow MITM attacks but otherwise they are "apparently" still secure. I say apparently as you generate your own key pair with BES (between the BES enterprise server and the user handset) but in theory there are ways to compromise this which it's likely western governments have, if they aren't quite so willing to admit to publicly like India etc...
that said. BB is still the best for enterprises who want security. Things like Intranet (well, native VPN) support and still not great on Android/iOS although KNOX looks pretty awesome and might start to rival it if other countries start signing off on it.