I'd like to be able to send email to the system whereby (a port of) the Subject would be the Title of the announcement and the Body would be the Description.
You could select the Visibility by including a tag in the email Subject. For example:
Subject: @Agents "Service Provider X - Notification of Intermittent Service"
I'm not sure how to control the scheduling feature, but I imagine that this could be done after the fact using the web interface.
... whereby (a part of) the Subject would be ...