It's an interesting piece, but I'd be more interested in analysis looking at the why behind that. What is it about the audience on the site, and the way the sites are presenting their content that is driving the non-FB sharing? Obviously this would need to be done with more sites than just those here. However, for a quick analysis, I nosed around three...<p>Billboard have Facebook and Twitter sharing buttons on their articles, but not G+, so it's fair to assume that the G+ sharing is going on on the G+ platform, not from the site itself.<p>Similarly, hovering over any image on TipHero presents share buttons for Facebook and Pinterest, and the bottom of their articles present a huge Share on Facebook button. However, no Twitter share button means they're getting nothing from that, and presumably not interacting in any way on G+ either.<p>There's a similar story again with Bleacher Report, which has Facebook and Twitter buttons (but interestingly no Twitter shares - possibly the wrong audience?), the same for every image, and Facebook, Twitter and G+ share buttons at the base of each article.<p>I think the takeaways from this are, Facebook is massive and cannot be ignored if you're publishing content, whilst everything else is dependent on whether or not your audience is there. But even if they are, the numbers in terms of engagement is going to be vastly lower, so can't be a priority.<p>My concern with this would be that, given that that's the case, this becomes a dynamo for Facebook, as the more they become the dominant platform, the less time anyone will spend working to build an audience anywhere else. Possibly Twitter is an exception to this, depending on the publication, but I wouldn't bet the farm on it.