Check these out:

http://www.itworld.com/security/297750/even-world-warcraft-tracking-you

http://www.ownedcore.com/forums/world-of-warcraft/world-of-warcraft-general/375573-looking-inside-your-screenshots.html

Steganographic identification of images in virtual worlds – like we’ve seen previously with printers:

http://en.wikipedia.org/wiki/Printer_steganography

Wanna bet that someone is going to try mandating this stuff real soon now?

ps: sorry if this post looks rubbish, it appears that WordPress have recently banjaxed their Android app and the editor pane is barely usable; the Link button generates HTML in a richtext pane, yielding chaos…