That is the massive power shift towards social platforms like Facebook.

In the not-so-distant past, much of the power and influence—both financial and journalistic—that traditional media entities used to have stemmed from their control over the distribution channels through which their content reached its audience. In other words, the printing plants and newspaper trucks and satellites and broadcasting facilities.

While all of those things still exist, they are no longer the only game in town when it comes to distribution, and therefore they are no longer the only game in town when it comes to making money from control of that distribution. Much of that power (and money) has shifted to Facebook.

This fundamental realignment of the planets in the media universe is the topic of a massive new report from the Tow Center for Digital Journalism at Columbia University, authored by Tow director Emily Bell and University of British Columbia assistant professor Taylor Owen.

The report states in its executive summary that “the influence of social media platforms and technology companies is having a greater effect on American journalism than even the shift from print to digital.” The takeover of traditional publishing roles by Facebook, Snapchat, Google, and Twitter raises “serious questions” about the future of journalism, it says:

These companies have evolved beyond their role as distribution channels, and now control what audiences see and who gets paid for their attention, and even what format and type of journalism flourishes.

As Facebook and other platforms have a huge amount of influence with the audiences that media companies want to reach, publishers essentially have to play ball with them whether they like it or not. Facebook has a user base of 1.8 billion people, many of whom spend close to an hour a day on the site. It’s the largest media entity that has ever existed.

While the company has routinely disavowed being a media entity for a variety of reasons (including the fact that media companies are not valued as highly by investors as technology companies), Facebook clearly plays a huge role in how people get news and information about the world.

It’s not just the platform’s size, as the Tow Center report notes. It’s the fact that the news feed algorithm determines what content gets seen by users and what doesn’t. The functioning of this filter, which is fundamentally an editorial instrument, is completely opaque to both users and outside observers, and yet it controls what is successful.

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While publishers can freely post to Facebook, “it is the algorithm that determines what reaches readers,” the report says. Cynthia Collins, social media editor of the New York Times, told the Tow researchers that this relationship means “We surrender so much control in terms of what gets read.”

Not only that, but because all news looks fundamentally the same on Facebook, media organizations that post a lot of their content to the social network risk losing their identity. In the end, in the minds of users (and brands), Facebook becomes the one responsible for delivering the news, and the media entity becomes just a supplier of commodity content.

The American Press Institute’s recent Media Insight Project found that only 2 of 10 people surveyed on Facebook could remember the source of the news they saw — and far more trust was placed in the person who shared a story than who produced it. “If we’re out here for branding and nobody even recognizes it,” said one publisher, “maybe it’s not worth it.”

Facebook[/hotlink], in particular, has begun exerting even more control over what kind of content gets produced because it has been trying to convince media companies to produce more video, including paying certain outlets (including the New York Times and BuzzFeed) millions of dollars in order to do so. As a result, many media outlets have shifted resources towards video.

In other words, Facebook, Twitter, and other services not only have a significant amount of control over who sees specific kinds of content because of their algorithms, but they are becoming more involved in creating it as well. Says the report:

Decisions made by Facebook, Google, and others now dictate strategy for all news organizations, but especially those with advertising-based models. Platforms are already influencing which news organizations do better or worse in the new, distributed environment.

So what kind of relationship should a media organization have with these powerful platforms? That depends on what kind of business you want to be running, the Tow report says. For some publishers such as BuzzFeed or the Washington Post, distribution and audience reach is of paramount importance, and so pushing all of your content to Facebook makes sense.

For others like the New York Times, which is trying very hard to become a subscription-based business rather than one reliant on advertising, such a relationship is going to be much more tentative one. The reach is necessary. But if the terms of the deal are not worthwhile, and users don’t “convert” into paying customers, then it is not worth doing.

Tony Haile, former CEO of media analytics company Chartbeat, told the Tow Center that there are two routes for publishers to take. One is to “jettison as many of their costs as possible and assume the mentality and framework of a low-cost/low-margin scale provider” to networks like Facebook, and the second is to “plan for a non-advertising future with multiple revenue streams.”

To some extent, traditional media companies are like horse-and-buggy operators trying to figure out how to survive in an automobile-centric world. They have large businesses, and many people still like their services, but the long-term trend is inescapable. And while Facebook and other platforms needs their content right now, it’s not clear that this will always be the case.

For the moment, Facebook’s needs and the needs of the media industry overlap, and the social network is willing to make deals. But that overlap could disappear quickly, and those who hitched their wagons to Facebook’s star could find themselves twisting in the wind.