Saks was down for about 90 minutes, coming back up about 4:15 PM (New York time). Given that those hours on a weekday would be an odd choice for scheduled maintenance, we asked Saks what was behind the Web absentia.
Saks spokesperson Carla Dunham E-mailed a brief statement saying that "we have decided to decline comment." (We said it was a statement. We didn't say it was especially illuminating.)
Sephora seems to have had a tougher time. Pingdom first detected that site's crash at about 1:00 PM (New York time) Wednesday, and it was reported to be back up three hours later. But when we checked the site repeatedly after that—as late as 3:48 AM (New York time) Thursday—the site was still down. It was even confirmed by this wonderful little site: http://downforeveryoneorjustme.com.
StorefrontBacktalk routinely tracks site downtime (we report any significant ones in our Twitter feed), and Sephora outages crop up more than any other single retailer we track. In fact, Sephora's downtime has become legendary.