For privacy advocates, it's a holiday miracle. Mark Zuckerberg's heart just grew three sizes. Facebook has just released a statement outlining several changes to Beacon, its online-advertising system which reports actions Facebook users take on other websites to their friends. The key takeaway? You can't opt out of Beacon completely, as some critics have asked, but reports on your activity — say, the fact that you just bought your girlfriend a ring on Overstock.com — won't be published without your "proactive consent," says Facebook. After the jump, the full statement.

Facebook Update on Changes to Beacon No stories will be published without users proactively consenting

We appreciate feedback from all Facebook users and made some changes to Beacon in the past day. Users now have more control over the stories that get published to their Mini-Feed and potentially to their friends' News Feeds.

Here's how the Beacon changes work:

- Stories about actions users take on external websites will continue to be presented to users at the top of their News Feed the next time they return to Facebook. These stories will now always be expanded on their home page so they can see and read them clearly.

- Users must click on "OK" in a new initial notification on their Facebook home page before the first Beacon story is published to their friends from each participating site. We recognize that users need to clearly understand Beacon before they first have a story published, and we will continue to refine this approach to give users choice.

- If a user does nothing with the initial notification on Facebook, it will hide after some duration without a story being published. When a user takes a future action on a Beacon site, it will reappear and display all the potential stories along with the opportunity to click "OK" to publish or click "remove" to not publish.

- Users will have clear options in ongoing notifications to either delete or publish. No stories will be published if users navigate away from their home page. If they delay in making this decision, the notification will hide and they can make a decision at a later time.

- Clicking the "Help" link next to the story will take users to a full tutorial that explains exactly how Beacon works, with screenshots showing each step in the process.

These changes are in addition to those made earlier to improve the notifications on partner sites as follows:

- Users were sometimes moving away from a page before a notification could be fully displayed. We changed the process so that we confirm the full display of the notification before any information can be sent back to a user's Facebook account.

- The notification appears more rapidly and is more clearly displayed.

There has been misinformation in the market about some key aspects of how Beacon works:

- Participation in Beacon is free for all partner sites.

- Beacon only allows for the sharing of specific actions on the specific sites participating in Beacon.

- Beacon only has the potential to display actions to a selection of a user's friends through News Feed and on a user's Mini-Feed.

- Facebook is not sharing user information with participating sites and never sells user information.

As with all its products, Facebook will continue to iterate quickly and listen to feedback from its users.