It is unfortunate that the communications mode has been bound by convention to the medium. It should be bound to the message. The urgency of a message should

It is unfortunate that the communications mode has been bound by convention to the medium. It should be bound to the message. The urgency of a message should be metadata associated with the message content regardless of the medium through with the message is transmitted and the client used to view it. How and when the content is delivered to a user should be a function of this urgency annotation and the trustworthiness of the sender. Someone who cold-calls you with an urgent communication is almost certainly a spammer. Of course, this will never happen, but a boy can dream.