Update January 18, 2011 at 12:52 PST
As reportedby Lance Whitney, Facebook has temporarily suspended providing cell numbers and addresses to application developers. Still, it's a good idea to at least consider not posting that information or limiting who can see it. This post shows how to delete the information. For details on how to control access, see my post at SafeKids.com.
The good news is that this is an opt-in feature, but there's a catch. Each time you install a Facebook app you're asked whether to allow access to your "basic information" and your "current address and mobile phone number," and if you click Allow, the information can be provided. Many people routinely do click Allow without necessarily reading the request for permission or thinking about the implications.
The safest way to make sure your address and phone number aren't passed on to developers is to not provide it all, and if it is there in your Facebook profile, to remove it. I especially recommend that parents talk with their teens about removing this information from their profiles.
Steps to remove contact information from your profile
1. Log into Facebook and click Home in the upper right corner.
2. Click Edit My Profile.
3. Click on Contact Information at the bottom of the left column.
4. Make sure that the Mobile Phone, Other Phone, and Address fields are blank.
Free Facebook privacy booklet
For detailed tips on how to configure your or your child's Facebook privacy settings, please see ConnectSafely'sA Parents Guide to Facebook, which I cowrote with Anne Collier.
Disclosure: Larry Magid is co-director of ConnectSafely.org, a nonprofit Internet safety organization that receives financial support from Facebook and other technology companies.
How to set up Google's two-step verification: To better protect your digital life, specifically your Google account, turn on two-factor authentication for your Gmail account. With a few minutes of setup time, your account will be much more secure -- with very little hassle.