Many social news sites are being highly critical today about the reports that Facebook's Data Scientists manipulated the Newsfeeds of hundreds of thousands of users. Apparently, Facebook was testing whether or not online emotions were contagious. They showed many negative news feed items to some users and positive news feed items to other users. They discovered that emotions influenced others. For a company that needs to be image conscious and protecting of its users' privacy, conducting this kind of experiment without permission seems to be a bad move. Not only does it unnecessarily toy with peoples' emotions, but it also raises questions about other experiments that Facebook may be conducting on people and the impact and privacy impact of that.
Facebook does many things well, but this is most definitely a face-palm moment for Facebook.