"E-mail as a platform really hasn't changed much over the past 20 years and there's a lot we can do to make people more productive," explained Rajen Sheth, group product manager for Enterprise Apps at Google, in a phone interview.
Pointing to a recent New York Times article that claims people in 2008 consumed three times as much information as they did in 1960, Sheth says that information overload has become a major issue for corporations. The average information worker, he says, receives 150 messages per day.
"People are spending way too much time just on e-mail," said Sheth. "There's definitely the need for e-mail to become a lot better."
Sheth says that testers spent 6% less time managing e-mail using Priority Inbox than they did without it. In conjunction with IDC's estimate that information workers spend 13 hours per week on e-mail, that works out to about 46 minutes saved per week.
Sheth concedes that some users may not see an immediate benefit from Priority Inbox if they don't take an active role in training the filter, but he also notes that the filter will learn what's relevant to users over time.
For high-volume e-mail users like Sheth, the time saved by using Priority Inbox is even more pronounced. "From my own personal experience, it took a couple of days to train it appropriately," he said. "But now it's literally something I can't live without. It takes out about 60% to 70% of my messages and saves me on the order of a half hour every day."
Such savings may have hidden costs however. Users may be tempted to process deferred e-mail during non-work hours. Ignored e-mail messages impose a wasted labor cost on the sender and supposed savings could be canceled if the sender has to resort to a more costly, time-consuming, disruptive activity like making a phone call.