Facebook CEO Mark Zuckerberg has brought the Beacon controversy to an end, apologizing to site members in the form of a blog post yesterday.

"I'm not proud of the way we've handled this situation, and I know we can do better," Zuckerberg wrote.

Beacon, which Facebook had touted as a new form of advertising, had come under almost immediate fire from privacy critics, MoveOn.org and, perhaps most importantly, Facebook users.

Responding to the controversy, Facebook had adjusted its opt-out process, making warnings bigger and more transparent. However, Zuckerberg's apology indicates that the social network squandered some of its users' goodwill.

To soothe concerns expressed by users, Zuckerberg announced that Beacon would now be an opt-in program.