Facebook took action to quelch a rumor that it had made public the phone numbers of all users of the social network.
Many users of the service Wednesday began circulating posts warning their friends that the phone numbers of their contacts are now visible to everyone on Facebook. The warning went something like this: “ALL THE PHONE NUMBERS of your contacts are now on Facebook!… please repost this on your status, so friends can remove their numbers and thus prevent abuse if they do not want them published.”
Full story: Facebook Moves To Debunk Phone Number Rumor