Photoshop art in wefail style

i am a big fan of the wefail-guys work like www.eminem.com or their recent project [URL=“http://www.dixiechicks.com/underground”]www.dixiechicks.com/underground. What i like to know is how they probably handle photos im photoshop to achieve their unique style, not the animation but the style and look of their characters. What do you think they do to the source-photos?? Thank you for your help!!!:te:

ps: sorry for the bad english!:sigh: