Today Apple has implemented Two-step verification for identity verification for users who are trying to recover a Apple ID whose password is forgotten or stolen by a hacker. The new system use a second iDevice to receive a security code via SMS or Find My iPhone application. This security token is required when trying to retrieve an Apple ID. Two Step Verification also makes it harder for your Apple ID to abuse on devices that do not have them.
The new system is similar to other web services and is currently only available in the U.S., UK, Australia, Ireland and New Zealand. The rollout to other countries will follow soon.