The developers have been listening to the community regarding the new 20 and 40 man raid instances coming out with patch 1.9. The tests being conducted have been invaluable to the development team and they have begun working on changes to make the instance better for the players. The new PTR going up will offer changes to the 20 man instance and the 40 man instance will see changes with a PTR closer to the end of the week. For more information on the changes being made to the Public Test Realm, click here.