Here's a little piece by Yarden Katz on science writing and its PR function. It goes over the public relation functions of popular science writing (at least in the press) and, of late, its function as the marketing arm "for elite research centers" (2). Towards the end it goes over how the major journals, the large research centers and the press together further the commercialization of science. It is not a pretty picture. There is definitely an element of show business in todays big science. Prestige journals role out hot new results the way movie studios role out big budget films. Universities see their academic stars and hustle to patent anything remotely patentable. Faculty strive for high visibility and the kudos and big bucks that come with it. It is possible that out of this show business ethic good science will emerge (just like it is possible for Hollywood to produce decent films). But it is pretty clear that truth is not the main target here, truthy suffices.
Gelman notes (here) that it was always thus. I think that he is partially right. Indeed, Katz's piece traces the roots of modern science writing back to Edward Bernays who wrote on how propaganda was required in a democratic society to keep the demos in line. He included within the purview of propaganda the dissemination of science to the public. So, the PR side goes way back. Nonetheless I think things have changed, at lease in degree. We now have an intimate alliance between business and basic science and the university. Once there was lots of money around to do science and there was no need to hype the work to get enough of it to do the work. Things changed when university funding started drying up and big business became more interested in "monetizing" basic research and government begun to squeeze university funding. When this occurred there developed a market for science PR, for treating science as just another thing to sell. Before, the selling did not go deep into the research community. The latter was insulated from the demands of market. Not now. Now everyone is pitching. And I suspect that one of the reasons that so many are wary of "experts" is that the idea that scientists are engaged in the disinterested pursuit of truth has been discredited. This piece gies one reasons to think that this suspicion is not entirely incorrect.