-
Cost/benefit analysis does not favor Google to do personalized news
every hard to determine the best news headlines to show you from the 100,000++ available news sources - the training data available about you is very sparse - the actual increase in conversion rate click through is very low - Google does not serve ads for news - against their policy
- Facebook determines the best content to serve you based on the behavior of your connections
the content set that your connections interacted with is smaller - the number of your connections are relatively small