A lot of misinformation in this thread.
If you want to see how it works, google Clares Law and Leaflet, it should throw up quite a few pages where you can download a PDF.
When you read through the leaflet, you will realise that checks are carried out not only on the individual who may be in danger and the person who may endanger them, but also the individual who is making the requests for information. They are invited in to speak face to face and have to provide ID documents. This is to ensure a check is made to prevent people trawling for information.
Secondly it doesn't follow that the individual who makes the request will be the person to whom the information is disclosed. At the initial contact, they'll simply be told "thanks for the info, we might be in touch". A decision is made as to who is in the best place to protect the person who may be harmed.
Lastly don't forget that the information passed is from a Computer Database.
Section 55 of the Data Protection Act 1998 states
1) A person must not knowingly or recklessly, without the consent of the data controller —
(a) obtain or disclose personal data or the information contained in personal data, or
(b) procure the disclosure to another person of the information contained in personal data.
As the legislation and procedure is so new and people quite rightly will be worried about the disclosure etc., you can bet your bottom dollar that anyone caught breaching this will be prosecuted and more than likely very publically.