“By Dec 31, 2013 the total volume of payments denominated in Facebook Credits (or any replacement introduced by Facebook) will meet or exceed $16 billion in a three month period.”

Facebook Credits are destined to grow much faster than Paypal did, given the large existing user base and the existence of large companies such as Zynga developing for the platform. They will reach PayPal's Q1 2009 TPV in a much shorter period of time.