Touting efficiency, news-readers give users the opportunity to scan hundreds of articles in a few moments and immediately delve deeper into the most interesting content. News-reading services do all the heavy lifting by aggregating the stories that match your interests, giving you more time to spend reading the news you care about rather than searching for it.
Beyond increasing efficiency, news-readers also allow for easy sharing of any stories of interest with your community of colleagues or friends. … Tablet apps make sharing simple, while still driving traffic back to the original source.
(Source: TechCrunch, How Tablets Are Transforming Business Intelligence)
I would throw Instapaper, Spool, etc. into this bunch. While aggregating and presenting the data is important, the ability to read and react to the news is equally important.