As has been rumored for some time now, Facebook on Thursday announced a new iOS app called Paper that uses a newspaper metaphor as a way of aggregating content from the social network, complete with topic-based sections and content selected in part by human editors. For traditional publishers — who already see the giant social platform as a competitor in the relentless ongoing war for digital attention — this is yet another shot across the bow from a company that dwarfs most of them in both size and reach. As Mike Isaac at Re/code mentioned recently, Facebook has been hiring editors who will help select the content that gets included in the new app. A spokesperson wouldn’t say how many have been hired, just that they are a “small team,” and that they will be looking for content worth highlighting from throughout the network, both from professional sources as well as individuals.