The report released Tuesday found that people who were fans of "your business", or friends of those fans, were more likely to buy something than those who were not fans.
Marketing on Facebook can help increase sales: Study
"A study from internet research firm comScore suggests that marketing on the Facebook can help increase sales."
http://timesofindia.indiatimes.com/tech/news/internet/Marketing-on-Facebook-can-help-increase-sales-Study/articleshow/14089484.cms
It's a quick read and an eye-opener if you catch its implications.