* The gaming industry is most likely driving a lot of this growth. I'm sure Machine Zone and Supercell are doing between $5M - $10M a day on FB alone.
* FB is re-defining attribution. They want to bring in big brands and are re-defining last-click to "Multi-touch". Their end game ofcourse is to say the reason why you decided to make a trip to Macys is because you first saw Macys content on FB.
* FB requires developers to send them analytics when they want attribution for Ads. This means that not only does FB have info about the install, but they have all the data about the usage, in addition to all their demographic data.
* FB still is the only reliable source for advanced targeting of ads. This has massive impact on ROI for performance marketers.
* FB by far has the best tools for advertisers with so many bells and whistles that resellers like Nanigans can make a healthy margin just by managing the optimization.
* FB allows any performance marketer to form a closed loop feedback system. Are CPI's on FB high? Yes. But if you know the LTV of your user (now possible with proliferation of analytics tools) you can afford to bid very high at volume (eg Uber) and still get a great ROI.