David Asman writes in "Getting Republicans on Message" at Foxbusiness.com that Republicans "..can't get much traction. We think its the message." Business leaders and politicians are concerned with remaining or staying "on message." This usage seems to be a new way to express the importance of maintaining a theme throughout a lengthy or complex communication.
We have text messages, email messages, mixed media messages, and of course, the almost quaint voice message (although most people now refer to these as voice "mail" which is a contradiction in terms).
UPDATE: 6-11-2012: Expect the messaging to continue in earnest during the Presidential election campaign. Use of the term "message" in this way reminds Cicero of these words: theme, point, subject, focus, mission, and idea. This usage also has the added attribute of leaving out the article "the," which Livia has addressed with aplomb.