"Facebook is not a news provider."
No, it is a social network, and even offline i get news from friends, sometimes that is personal, other times it is exciting world news... Other times it is about Justin Beiber (or Jedward, but then i know people who went to school with Jedward, and apparently they were annoying even before they became famous)
Despite this, there are a number of facebook pages which serve interest groups, and often post news. I believe a majority of my facebook feed is from these groups rather than friends... 'i fucking love science' and 'science is a verb' are two of my prefered sci-news sources.
"Sadly, I think a great many voters in the US have successfully blocked
themselves from any and all sources of valuable information..."
And this is of course a problem with using facebook, or any other 'free choice' - of couse even with main-stream media sources (like Fox/CNNMBC? You know, Things Jamie might agree are 'news sources') are heavily selective in how/what they report.