OTOH Facebook just stopped development on their PayPal killer, because their ad revenue is going through the roof and they want to focus on that instead.
thanks to a sudden uptick in brand and self-service sales, Facebook's ad sales team <http://www.businessinsider.com/facebook-state-of-affairs-2009-9#> is -- in the words of one source -- “beating the shit out of its numbers."
http://www.businessinsider.com/facebook-state-of-affairs-2009-9
A lot of people early on thought Google would never make money either...