In a culture like ours, long accustomed to splitting and dividing all things as a means of control, it is sometimes a bit of a shock to be reminded that, in operational and practical fact, the medium is the message. This is merely to say that the personal and social consequences of any medium - that is, of any extension of ourselves - result from the new scale that is introduced into our affairs by each extension of ourselves, or by any new technology. ~ Marshall McLuhan
A news story without video is not appropriate for TV news, shaping not only how stories are told, but which stories are told.
This notion ties in with Noam Chomsky's notion of "Manufacturing Consent" though Chomsky uses the term as a recognition of conscious manipulation while in this synthesis with McLuhan I'm just as interested in it as an unanticipated effect of communication technology.