Is the Google-Facebook duopoly that has dominated digital advertising finally facing serious pushback? I'm seeing lots of tidbits and trends suggesting that other players, especially those focused on quality content, are finally getting some love from readers, advertisers and subscribers.No, the Big Two aren't going anywhere. And perhaps some of this is just wishful thinking, but there are plenty of data points worth pondering, not least the series of self-inflicted wounds that have hit both Google and Facebook since last summer.There was the election-season controversy over fake news, distributed by Facebook and financed by Google's Ad Sense accounts.  There was Facebook's repeated series of mea culpas last fall over badly flawed viewer-measurement tools. And there was the recent YouTube boycott by dozens of companies that didn't like seeing their brands popping up in ads next to (and financing) vile videos by extremists.Facebook still hasn't defused concerns about its handling of fake news. Among other initiatives, Facebook is now running newspaper ads telling people how to spot such posts. That somehow seems like a joke post itself, from The Onion or a similar site, but it's not.Facebook also said it would add another 3,000 moderators to its 4,500-person team reviewing objectionable content, as more criticism erupted after live streams on its site showed suicides and the murder of a random elderly passerby.Those issues all have undermined advertiser and reader opinions about the Big Two,  encouraging some to consider alternatives.As well, many have reasonable concern about the sheer dominance of the two companies. A recently released analysis by big ad buyer Zenith estimated that Google and Facebook combined captured $106 billion in digital advertising last year, or roughly 20 percent of all advertising across all formats around the world. Google received about three-fourths of that money.Those are stunning numbers, driven by advertisers' belief in the value of the Big Two's targeted user data. But at least some publishers are getting savvy about data too, tapping new ad-tech capabilities and offering increasingly sophisticated direct buying options, both directly and through emerging platforms.They're being helped by ad-tech companies such as Skimlinks, which are feeding publishers the kinds of deep data that advertisers want, data that previously only the Big Two could provide, while unlocking new revenue opportunities in e-commerce and elsewhere.Further, one recent analysis suggested that, when search-engine revenues are taken out, we're already seeing healthier growth in publisher revenue:"...then the duopoly market share changes to 55% in 2016. While that share had risen from 49% in 2015, 21% of overall ad spend growth was going to Google and Facebook’s many frenemies," the analysis suggested.Those numbers may accelerate this year. On the eve of the NewFronts, CEO Sir Martin Sorrell said WPP would direct $200 million this year to Snap. It's part of a conscious effort from the world's biggest ad buyer to build what Sorrell has repeatedly called "a third force" in the digital business beyond Google and Facebook.Snap has also found friends among major publishers such as Mashable, which are producing stories for Snapchat's Discover section, one of the web's hottest pieces of digital real estate."Snap has given us a valuable, loyal, young audience of millions who can be hard to reach on other platforms," Mashable's chief content officer Greg Gittrich told an Australian outlet. "It's very profitable for us."Now, more than 60 publishers of all kinds – networks, newspapers, digital-only sites – populate Discover. Last year, Snap paid out nearly $58 million to those outlets – about six times the previous year's total – under an evolving set of revenue-sharing and licensing arrangements as it experiments with ad formats, content mix and more.In building its Discover section, Snap asked publishers to specialize in specific categories (tech for Mashable, for instance) and to avoid "tabloid-like fare" that might provide a short boost to viewer numbers but undermine the overall experience. It banned fake or deceptive news stories outright, and has said it would rely on "editors and artists rather than clicks and shares" to determine what gets posted. Accordingly, Snapchat has attracted higher-quality advertisers too.And Snapchat isn't the only site running to quality. The same analysis that found signs of publisher revenue growth (beyond search spending) also found that the growth was largely focused on sites that provided quality content and a less cluttered user experience that attracted premium advertisers.The post-election backlash over fake news has provided prominent publishers such as the New York Times and Washington Post with an opportunity to highlight their quality while building their subscriber base and attractiveness to advertisers.It's important to acknowledge that Facebook and Google aren't going anywhere. And they're spending significant resources to move into sectors such as the Digital Era's version of "TV,"  with subscription services, long-form scripted episodic programming and more, backed by programmatic ad buying and highly targeted data. Success there would represent the Duopoly's capture of yet another ad market. And they're making big runs at budding opportunities such as live streaming and virtual or augmented reality.But the recent signs of success by others suggest that eventually, big can be a bit too big for comfort. Inevitably, it will spark concern and reactions that in turn give new opportunities to quality publishers, premium advertisers and the ad-tech companies that can help them compete against two of the world's richest and most successful companies.