What's The Deal With Facebook's Ad Prices?

Now that sponsored stories have had almost half a year to germinate, a growing number of pundits are saying that these ad units perform about 50 percent better than other types of promotions on the site.

The better the performance, the more cost effective the ad gets. And explains why Facebook can keep prices constant while growing inventory.

However, sponsored stories haven’t expanded the promotional inventory that greatly simply because the ad units rely on users engagement with brands.

“Sponsored