If you cannot see the above video, this part of Pottermore is clearly going to be more of an MMORPG than the existing Pottermore community. Think Warcraft, not Zork.
The developers have invented several new mini games, and they're going to give players a chance to fight duels in the Hogwarts Express train and answer trivia questions. The setting for the game suggests that the developers have done their best to replicate the scenery from the Harry Potter movies.
Update: Pottermore Insider is late to breaking the news and has more details.The new site is officially called Pottermore at PlayStation Home. Players will be able to dress their avatar in a variety of wizarding outfits, including school robes. Members of Pottermore who have been sorted into a House will be able link their Pottermore account with their PlayStation Network ID and gain access to additional content and spaces.
According to Sony, the new site is expected to launch in April 2013. You will need to have a PlayStation 3 in order to visit, but it does appear that the site will be free.