The Zeitgeist wins the day

Bowing to user protests organized mainly by MoveOn.org, as well as a lukewarm reception from marketers, Facebook has put the Beacon on a short leash.

The Beacon reveals items people have purchased from partner sites, including Fandango, Overstock and Blockbuster. News of the purchases appear on friends' News Feeds.

Users may choose to opt out of the Beacon feature, but many pleaded confusion in this regard. More than 60,000 users joined MoveOn's Petition/Facebook group, Facebook, stop invading my privacy!.

Last Thursday Facebook enacted a change that asks users to "opt in" before it publishes information to their friends.

Adam Green of MoveOn called Facebook's new opt-in "a significant step in the right direction."

"It also says a lot about the ability of Internet user to band together to make a difference," he added.

According to the Associated Press, the Beacon backlash "illustrated the delicate balancing act that Facebook must negotiate as the company tries to cash in on its popularity without alienating the users fuelling its success."

The AP also observed that the service may lose luster for advertisers, considering fewer people participate in services where they have to opt in. Some have already become hesitant about moving forward: Coca-Cola put its campaign on hold, and Overstock has pulled out entirely, according to Wired.

The Beacon was one component of Facebook's three-part ad plan, unveiled in early November.