Facebook bought WhatsApp in February and today announced that it's ripping its messaging app out of the core Facebook app. What has always been fascinating/tricky about the messaging system is that there is no open protocol for apps to talk to one another. Unlike email where I can email you from Gmail and you can respond via Yahoo, with messaging we both have to be on the same app.
This makes a messaging network extremely valuable once it's at critical mass. It does, however, lead to users downloading different apps to message with different relationships. FB Messenger for loose relationships, WhatsApp for international friends, and iMessage for close family and friends.
When betaworks surveyed people's homescreens at the end of 2013 they found that of the people with messaging apps on their homescreens, 88% had a non-Apple messenger.
The ecosystem is very, very fragmented.
With Facebook's purchase of WhatsApp and their push for an independent FB Messenger app, they're moving towards a privately owned messaging protocol. How long until we see WhatsApp and Facebook users able to message each other? Once that occurs, the value of the combined services increases exponentially. (Thanks Metcalfe's law).
Soon after comes developer support to allow 3rd party apps to leverage the sharing and relationships of messaging (which WhatsApp already has tested with BuzzFeed).
The next true platform is mobile messaging. Facebook knows that. They already played this game with their developer ecosystem on the web.
It's deja vu all over again.