Facebook has officially begun rolling out the new Timeline feature to its entire 800+ million user base. Announced in September, the move represents a complete reconceptualization of profile pages, where instead of just the most recent updates, users will see a timeline of life events containing photos and other updates that stretches back to when you joined Facebook. As Zuckerberg puts it, Timeline is the story of your life.

Anyone viewing your Timeline can click back to any year where there are updates and see what was going on at the time. Facebook automatically selects the most important updates and highlights them on your profile page, though users can of course remove certain updates and highlight others that might be important to them.

As you would expect, the idea of reviving old -- and potentially embarrassing moments -- in their profile pages hasn't sat well with some users. In an effort to appease critics, the social network is giving users a seven-day review period to tweak their Timeline before it goes public for viewing by others on December 21st. (Update: Facebook's PR people wrote to clarify that December 21st is not a deadline for everyone to review and set up their Timeline. The seven-day review period starts counting whenever users opt-in to the new Timeline profile. There's no announced date for when Facebook will make the change mandatory but the opt-in period will apparently last for a few weeks.)

Users can get the new profile page now, by going to the Introducing Timeline page and clicking "Get it Now".

Facebook first rolled out Timeline in New Zealand last week in order to monitor speed and performance before a global rollout. Before that it was also available to developers -- as well as faux developers interested in trying out the feature early. According to Facebook, over one million people signed up for the beta.