On Wednesday afternoon, visitors to The Washington Post’s Web site were greeted with a new feature on the home page. Along with the news of the day was a window prominently displayed in the upper right corner showing a list of readers with public Facebook profiles who had recommended—or “liked,” in Facebook parlance—Post stories to their Facebook friends.

The new feature seemed straightforward enough: a social-media twist on the old “most emailed” list. But by Friday, the Post was facing an insurrection from users concerned that, among other glitches, the service had no easy opt out feature. Editors quickly held an online question and answer session, explaining the feature and pledging quick changes, which were to go into effect today.

For those of you who think of all social media as one big amalgamation called YouFace, here’s a quick explanation of the mechanics of the relevant part of the Facebook experience: Facebook lets its users comment on what their friends post, or simply click a thumbs-up button that says “I Like This.” If you decide to “like” something, your friends then see the item in their News Feeds; if they, in turn, decide to like it, their friends see it, too. (A News Feed is a personalized and continually refreshed list of each user’s friends’ activity, until now only viewable on Facebook.com). As individual Web sites attempt to capitalize on traffic, and thereby ad dollars, from social media sites like Facebook (and Digg and Delicious), little blue Facebook buttons are increasingly popping up at the end of stories and videos and various Web items to make it more convenient for readers to “like,” or recommend, those stories to their Facebook friends.

None of that is news. What is news is that Facebook News Feeds are now showing up on third-party Web sites that are not Facebook. And if you haven’t set up your privacy settings tightly enough, your actions on Facebook, as they pertain to those particular third-party sites, could be broadcast by said third-party sites. Right on the home page. On the upper right hand corner. With your grinning profile photo in all its glory.

This did not go over well with some readers.

An editor’s note from Post managing editor Raju Narisetti explaining the new feature and how to opt out was published the same time the application launched Thursday. The note quickly drew a stream of comments from users, many of whom were worried about violations of their privacy; in addition, Narisetti said, he received more than 200 emails expressing confusion and displeasure with the new feature. (At the same time, he noted in a phone interview Friday, the site had received four million visitors since the module was launched.

Narisetti told CJR that he takes every complaint seriously, but was quick to remind that the site had received four million visitors since the module was launched, and though he acknowledges it takes more effort to write an email than to click a button, pointed out that 336 clicked the “Like” button featured at the end of the note to share it with their friends, proving that some, indeed, were fans of the new feature. (Although it’s possible some of those clicks were meant to spread word, i.e. warn, of the new feature.)

Nevertheless, Narisetti had a bit of a problem on his hands. On Friday, he posted an announcement that the Post would respond to the criticism by providing a full opt-out feature and even giving users the option to block the window from popping up on the site altogether. Then Narisetti and Bret Taylor, a Facebook executive, held an online question and answer session with Post readers to explain the changes and how to navigate the new feature.

Alexandra Fenwick is an assistant editor at CJR.