Its just that ICANN board gave final approval for creating a separate domain for pornography and that will be ".xxx".On 10th december,2010 the board decided to enter into an agreement with ICA Registry for .XXX sTLD, subject to GAC consultation and advice.This is finally achieved on 17th march,2011.Here is the whole board resolution,if you are interested.
So,finally the net has its own official "red light" area.Porn sites are not bound to register but they are expected to do so because otherwise the domain name might be gobbled up by some other competitor.It was also seen that porn industry is usually very fast in adopting the changes.
In order to register they have to ensure that their site does not contain any child pornography material or fraud or malicious code(to install virus into the user's PC).
So this address will provide some reassurance to the customer and the end-user.If any of you wondering if somebody will actually register into the registry or not,then a small data for you guys--therre is already 200,000 requests to register name into this new domain-and that is within 48 hours!!!!!!!!!
some info about ICANN
To reach another person on the Internet you have to type an address into your computer - a name or a number. That address has to be unique so computers know where to find each other. ICANN(Internet Corporation for Assigned Names and Numbers) coordinates these unique identifiers across the world. Without that coordination we wouldn't have one global Internet.ICANN was formed in 1998. It is a not-for-profit public-benefit corporation with participants from all over the world dedicated to keeping the Internet secure, stable and interoperable. It promotes competition and develops policy on the Internet’s unique identifiers.