The screenshot above is taken from Cakewalk, a music technology firm based in the Boston Greater Metro area. Cakewalk is an Amazon customer and its ecommerce site was directly affected by the outage. As can be seen from their message, the outage resulted in an interruption to an existing web campaign, and obviously no ecommerce revenues were possible during the approximately two day outage. In addition to the lost revenue, as web staff scrambles to compensate for the outage, errors can be made in reconfiguring sites with workarounds. There's no way for the GlitchReporter to know the cause for sure, but Cakewalk's ecommerce store is now getting a 404 on the store's home page (see below).
These failures are infrequent, and failures will happen in the cloud just as they happen to internal data centers, but there are important differences, too. As the GlitchReporter noted not long ago with a Gmail cloud outage, the scale and complexity of cloud resources may reduce the frequency, but perhaps not the cascading effects of failures across enterprises. Perhaps more importantly, because technical communications from big company cloud firms (Microsoft, Google, Amazon) tend to be sketchy during such outages, customers could not be blamed for thinking (even if erroneously) that they might be better able to work around and plan for failures that occur inside their own data centers.