WoW Screenshot Watermarks?

An article called Looking inside your screenshots on Ownedcore alleges the use of digital watermarks in World of Warcraft screenshots that include the player's account ID, a timestamp, and the IP address of the realm where the shot was taken, noting this can be used by Blizzard to identify hackers as well as the location of illicit private servers for the MMORPG. They say they can confirm this functionality was added sometime between 2008 and 2010, and note the concern that this opens up WoW players to potential exploitation. Thanks Ant via Slashdot.