Explore Social Media's Link to Database Marketing

We read surprisingly little about social media and database marketing. Why is that?

The primary goal of database marketing is to capture the kind of information that can be used at a later date to either facilitate a purchase or reduce marketing expense to a customer unlikely to purchase again.

So wouldn't it seem that capturing social media information in a database should be a big deal? By having this information, you can truly learn how customers with prior activity will perform in the future.