Agreed. I would want "No lock-in" for IM to be a requirement. I wonder whether or not pure volume - e.g., Facebook Messenger - would be enough, however, to driv

Agreed. I would want "No lock-in" for IM to be a requirement. I wonder whether or not pure volume - e.g., Facebook Messenger - would be enough, however, to drive people in that direction even without the interoperability with other systems. (I am not a Facebook user; just recognizing that they do have market share on their side.)