The latest sign is Facebook’s announcement yesterday that it is retooling its Trending section, which lists topics that are being widely discussed on the site and that Facebook algorithms figure would be of interest to each user. New algorithms will try to weed out topics that are based on just one news report—the better to eliminate “fake news.” The new algorithms will look instead for topics being covered by several media outlets, trying not to be misled if several outlets cover a fake-news outbreak because it’s fake news. The personalization feature will also be discontinued; every user in a given country will get the same list of Trending topics.

Facebook is clearly making the change because of controversy that arose after the election, when some people speculated (without reaching a conclusion) that fake news that was spread via Facebook’s vast reach might have influenced the outcome. Facebook really does not want to be—and cannot be—the fact checker of billions of posts, yet it could not fail to act in response to the controversy. The company last month announced a plan to encourage users to flag fake news and to discourage them from sharing disputed posts. Yesterday’s announcement was the next step, and more will likely follow.

The reality that all of us (including Facebook) must accept is that 44% of all U.S. adults get news from Facebook. So says Pew research, in a study that is now a year old and probably understates the real number. No other media outlet comes near that figure. Facebook emphatically does not want to be considered a news media outlet, but if a plurality of U.S. adults get news there, then that’s what it is.

Google announced that it had evicted 200 publishers from its AdSense network in November and December, some of them for being fake news sites. Again, the motivation is clear. Google took heavy criticism post-election when its algorithms gave high placement to a fake news item claiming Donald Trump had won the popular vote. Like Facebook, Google hates the idea of being part of the news media; its Google News site amalgamates stories from other sources and is entirely algorithm-driven. But its massive audience—over a billion monthly active users as of a year ago—makes it a media titan, like it or not.

One more factor: As media audiences move steadily online, remember that Google and Facebook together accounted for 99% of all the growth in online advertising in last year’s third quarter. It’s a duopoly. How incumbent news media will finance themselves becomes murkier by the day.

How will the news business look in five years? I have no earthly idea. But that’s the world that all business leaders must try to envision.

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