Amazon had issues in 1 of their 5 datacenters and it was the first time in a very long time for them to have any issues.
They still have one of the best availability records even with this outage.
The particulars of this outage are still being discovered and reported on but it seems to boil down to some sort of network failure caused one of the 4 zones in the virgina data center to start a massive remirroring of the ESB (elastic storage block) services. Which as a result saturated their management systems that control the cloud in the datacenter.
While it's terrible for all those that suffered from it many companies like netflix (that runs inside amazon) didn't go down at all because they planned for such situations by spreading loads across multiple zones in multiple datacenters.
I think most will not move off of amazon just becuase of one outage but instead will learn to better understand and use the cloud in such a way that issues in one area will not bring them down in the future.