A couple years ago, rich-media ad units were all the rage. Oh snap! Videos and expandable banners and Twitter streams and buttons on top of buttons. "How can consumers and big-budget brand advertisers not come to love these interactive ads?" many proclaimed.
A year ago, Facebook made zero money from mobile advertising because it had yet to launch a mobile ad product. Now mobile accounts for 20 percent of advertisers’ spending on Facebook, according to social ad firm Kenshoo Social.