Bloomberg Businessweek dives into email and how it relates to retailers, and especially holiday shopping. Numbers from the DMA make a compelling case with email raking in $39.40 in sales per dollar vs $12.90 from social networks.

“Even as retailers debate the efficacy of social-media marketing on Facebook and Twitter, they have no doubts about the power of a decades-old technology to drive sales. The killer app is called e-mail.

Retailers as disparate as Williams-Sonoma Inc. and Home Depot Inc. have become much better at tailoring e-mails to specific customers rather than the one-size-fits-all blasts that once dominated this type of marketing. Measured by sales per dollar spent, e-mail outperforms social-media advertising three to one, according to the Direct Marketing Association, a trade group founded to provide accurate marketing data. That explains why retailers will send 19 percent more e-mails this year.

“Compared with social-media, e-mail marketing will never be sexy, but it depends on what’s sexy to you. In my opinion, making a high profit rate and bringing in a lot of incremental dollars is very sexy.”  said Ted Wham, a vice president at Responsys Inc. 

Well, we definitely think email is sexy! Read more in Businessweek.