It appears in today’s Hong Kong newspaper (Apple Daily) that unauthorized Facebook credit transactions were carried out for a Facebook user.
The user claims that his credit card was used to purchase Faecbook credits 5 times recently for a Facebook game that he never plays. He mentioned that he has registered his credit card information as that is required as part of the Facebook Developer registration process.
He has already reported the case to Hong Kong Police and Facebook.
For details of the incidence, please see: http://hk.apple.nextmedia.com/template/apple/art_main.php?iss_id=20111116&sec_id=4104&subsec_id=11867&art_id=15805789