Is Amazon's Mechanical Turk a digital sweatshop?

"The wages offered on Mechanical Turk do not seem very enticing. Three cents for copying the product codes and prices from a digital receipt. Five cents for identifying a series of images as adult content. $1.13 for writing a verbatim transcript of a 4 minute and 2 second audio clip." Who would line up for a job that pays so little? The answer might surprise you. [priceonomics.com via Matt Richardson]