Facebook, the most popular social media service, isn't primarily known as a news source. Yet a new Pew report found that 47% of all adult Facebook users (30% of all U.S. adults) report that they encounter news on Facebook. Strikingly, over two-thirds of Facebook news consumers regularly encounter news about people and events in their own community -- including about 44% who see stories about local government and politics. In contrast, just 55% of Facebook news consumers see news of national government or politics on Facebook.

According to the Pew Research Center, Facebook may provide a way to engage community members who otherwise generally "tune out" on the news:

"Facebook exposes some people to news who otherwise might not get it. While only 38% of heavy news followers who get news on Facebook say the site is an important way they get news, that figure rises to 47% among those who follow the news less often. 'If it wasn't for Facebook news,' wrote one respondent, 'I'd probably never really know what's going on in the world because I don't have time to keep up with the news on a bunch of different locations.'"

Facebook may prove especially helpful for engaging youth in community news and information. Last year, Pew found that only one in four U.S. adults under age 30 say they enjoy following the news a lot -- a rate that has been dropping steadily since 2008. In contrast, 42% of those age 30-49, and 49% of those age 50-64 avidly follow the new -- as well as 58% of U.S. seniors.

In this week's report, Pew observed that those aged 18-29 encounter news on Facebook across topics about as often as people in older (and inherently more news-engaged) age groups. "It may be the incidental nature of Facebook that ultimately exposes more people to news there. Indeed, the more time one spends on the site, the more likely they are to get news there."

Pew found significant overlap between news people encounter on Facebook and what they get via other media. "About 72% say that the news they get on Facebook is news they tend to come across elsewhere. And the same percentage says that most of the sources they 'like' or follow are ones they also read, watch or listen to outside of Facebook. One respondent explained, 'I follow a local TV station, because they post breaking stories before they're on the air. It also helps with traffic problems due to wrecks or construction.'"

In terms of engagement, how do people interact with news on Facebook? Pew found that about two-thirds of Facebook news consumers at least sometimes click on news links to check them out, and 16% do so often. Nearly as many at least sometimes "like" or comment on news stories, and 19% do so often. Furthermore, about a third sometimes discuss issues in the news with other people on Facebook, and 6% do so often.

Over 80% of news "sharers" told Pew that they encounter on Facebook news about people and events in their own communities -- including 65% who specifically find news about local government and politics there. In contrast, only 69% Facebook news sharers encounter national government and political news there.

Why do people share news on Facebook? Pew notes: "The most common reason why members of this group post news links is to pass along information they think is important for people to know. A vast majority, 89%, indicates that this is a major reason why they post or share news. The next most common reason is to create a discussion among friends around an issue or event (70%), closely followed by the desire to make a statement (67%)."