He mentions around the 3 min mark that lead generation generates more revenue than direct payments (and then goes on that topic for a bit).
Mark Pincus talks about it here - http://markpincus.typepad.com/markpincus/2009/11/my-take-on-...
Peanut Labs backs it up with independent research - http://peanutlabsmedia.net/2009/11/02/survey-finds-arrington...