Want free coffee and got an iPhone? Use Jonathan's Card (Updated) | TUAW - The Unofficial Apple Weblog
But nothing is ever simple. There have been allegations of viral marketing campaigns and dishonesty. While the experiment has garnered lots of people a free cup, it created controversy because some people can't believe that others are willing to do something nice.
I believe that this experiment was genuine and a good example that not everyone is a cynic.
Starbucks shut down the account on August 12, 2011, but Stark intends to continue the good will by continuing to promote a "Pay It Forward" coffee strategy with a slightly different strategy: Buy the next person in line's coffee - No Starbucks Needed. See the latest update - http://jonathanstark.com/card/.
Follow @jonathanscard on Twitter to see updates on this evolution of the experiment.