Google is there when you're in the buying mindset. "I need car insurance, let's google car insurance" that's worth $40 a click. And there's return on investment from that too.
Facebook is fantastic for advertisers what it mastered is targeting. It knows EVERYTHING about you. However it is at a disadvantage from google in that, you're not in a buying mindset when you're on the site. So as an advertiser the clicks are worth less.
Reddit could enter facebooks space. Your comments and forum activity could be data mined to build an advertising profile. However, they haven't really mastered that yet.
Facebook is fantastic for advertisers what it mastered is targeting. It knows EVERYTHING about you. However it is at a disadvantage from google in that, you're not in a buying mindset when you're on the site. So as an advertiser the clicks are worth less.
Reddit could enter facebooks space. Your comments and forum activity could be data mined to build an advertising profile. However, they haven't really mastered that yet.