The restaurant sold out of 3.5 million Rob Dyrdek cups in a little more than a month.
New York Times article: http://www.nytimes.com/2009/03/18/business/media/18adco.html
additional RB cup sightings:
http://www.thrashermagazine.com/articles/burnoutleftover-radical/
http://enclavenh.blogspot.com/2009/02/carls-jr-rob-dyrdek.html
http://www.qsrweb.com/article/99945/Carl-s-Jr-plans-series-of-skater-Rob-Dyrdek-promos