Facebook now open to anybody with an email address

As expected, Facebook has officially opened the site to anyone on the planet.

However, the rules governing whose profiles you can view haven’t changed. As I wrote before,

I’m sure the first thing people will do is compare Facebook to MySpace. However, unlike MySpace, Facebook has pretty good privacy controls in place that a reasonable number of people use. New people will only be able to see others in their geographical network. So unless college students join geographical networks in addition to their college networks, they should still be inaccessible to the random searcher.

Facebook is obviously trying to do a better job communicating changes to its 10 million college users than it did with its botched news feed launch.

Here’s the full “How this expansion affects you” message, which was shown to every Facebook user starting this morning:

Now you can get all your friends on Facebook—people who couldn’t get on before because their schools didn’t offer email addresses, because they went to work instead of college, because they graduated before Facebook even existed, or for any other reason. They can join regional networks and see other people in those networks.

Facebook’s network structure is really important in making this expansion possible. The network structure means that the only people who can see your profile are your confirmed friends and the people in your networks. All college, high school, and work networks are authenticated networks, so they are exclusive to the people in them. This means that new people in a regional network can’t see your information unless you are in that same regional network. If you have added a regional network, you can restrict who can see your profile, or remove that network affiliation.

We already give you tight privacy controls, and with this expansion we’ve added even more. You can prevent new users from seeing you, and you can control what they can see about you on the site through some of our new search privacy controls that we added last week.

If new regional users cannot authenticate through an email address, we prompt them to authenticate through a mobile phone number. This makes sure that they are real people.

People who don’t verify their mobile number will be presented with security tests—the word-in-a-box images—whenever they attempt to message, poke, or add another person as a friend. These tests can be read by people, but not computers. This means that anyone getting through these tests is a real person.

We’ve added “Report” links in many places around the site. We’ve been using these for some time to let you help monitor the site. Some people already try to abuse the site, so when users report something, we follow up on it and quickly take it down if it violates our Terms of Service. This has worked well; so if you see something suspicious, offensive, or inappropriate, please report it.

We are putting as many controls in as possible and are always looking for new ways to protect our users from spam and inappropriate behavior. Remember that you control what you do on the site, including whom you add as a friend, and what information you make visible to the people around you.