I just wanted to take some time to drop in and reassure people that the change to the dots is intentional as a part of ongoing balancing that we have been doing. It is not a bug.
Just so that everyone knows a bit more the approximate damage reduction is 10% for "Curse of Agony" and "Corruption" for the average Warlock.
*Edit- Changed "and" to "to". Also edited out Affliction to read correctly as "Corruption".
http://forums.worldofwarcraft.com/thread.html?topicId=62082150&pageNo=1&sid=1#1