Sears' explanation—the system sent confirmations before checking inventory but sent the cancellation E-mail almost immediately—misses the point. It's 2012, not the dawn of E-Commerce. Inventory is online. Customers don't need to be reminded that they just placed an order, only notified that their order will be honored. There's no reason for two E-mails, nor is there any excuse for confirming an order by E-mail before checking inventory. That will take an extra 30 seconds? Five minutes? It's E-mail. Nobody expects sub-second response times, not even customers. They do expect a "confirmation E-mail" to confirm they've made a purchase—and it's long past time for retailers to get that message.
Didn't we learn this lesson last year with Best Buy? On Black Friday morning, a Houston-area couple got up at 2:00 AM to order thousands of dollars' worth of appliances from Sears. They got their order confirmation E-mail, went back to bed—and woke up to find another E-mail telling them their order had been canceled. Then the appliances were delivered, but charged at the regular prices thousands of dollars higher. It took a local TV station's cage-rattling to get Sears to honor the Black Friday prices.