Retailers Fight Exile From Gmail In-Boxes - NYTimes.com

From a snapshot of Google's recent and controversial Gmail inbox redesign

"The change to Gmail, though, strikes at the heart of retailers’ marketing tactics. Eighty percent of marketers are investing more in e-mail this year than last, according to a study by Forrester Research and Shop.org. And with nearly half a billion users, Gmail is a major part of that strategy.
Although Google is also filtering other messages into secondary in-boxes, like sending Twitter and LinkedIn notifications to the social tab, retailers say they have the most to lose."

Retailers Fight Exile From Gmail In-Boxes - NYTimes.com