They are careful to make the following disclaimer:
Note: It was not the intention of this experiment to make any particular group look bad, reinforce stereotypes nor to further a hidden agenda of any kind. The actions of a few members in a group should not, of course, be used to judge the whole group.Of course, there's plenty of online discussion, questions, and ranting about the meaning and significance of the results.
For those who care, it is technically a crime to fail to return a lost wallet in Illinois, where the test was performed (720 ILCS 5/16-2 "Theft of Lost or Mislaid Property".) This may or may not be widely known amongst the general population however.
(Via Clicked.)