Hi David,
I found the article well written and insightful. Perhaps I can help:

The phrase "...is the new black" means "...is the latest trend/must-have item" and I believe it has been in use long enough for it to be well known by the majority of his audience and for them to be able to extrapolate what he means with ease.  What he posits is that the general public now wonders exactly where we can go for news which is as objective as possible and well curated (I'm sorry, I love the term - see below) and I think it would be tough to argue credibly against that.

On the phrase "news curation", the paragraph before the one you quoted at length began: 
"Many of us feel that professional news curation, editing, failed us deeply." 

So there you go, he explains that, for the most part, he means 'editing'. However, he doesn't simply use the word "editing" is because his entire premise is that the selection of what is put at the forefront of our news services (for which 'news curation' is an excellent term i.e., curation requires the selection of the most appropriate pieces to highlight from a collection of items) will be performed not only professional editors but rather by a mix of editors and populist "audience participation." I think most of us would agree that he should not have referred to the 'audience participation' as 'editing'. 
At the moment, the selection balance is rather heavily on the side of the audience (sometimes entirely) and he was arguing for more editing, something which I would DEARLY love to see. I'm tired of the online front page of my newspaper being littered with celebrity births, diets and anything titillating because that's what my fellow readers have clicked on most.  

I hope that helped :)