When it comes to IT you must always be prepared!
Here are excellent posts that provide you direction and insight from lessons learned.
8kmiles Blueprint for Achieving High Availability: http://cloudblog.8kmiles.com/2011/04/29/design-for-failure-architecture-blueprints-for-achieving-high-availability-in-aws
How Netflix plans for Cloud failure: http://techblog.netflix.com/2010/12/5-lessons-weve-learned-using-aws.html
RightScale CTO, Thorsten von Eicken in regards to the Amazon outage:
Lessons Learned: http://blog.rightscale.com/2011/04/25/amazon-ec2-outage-summary-and-lessons-learned
Follow up to Amazon response: http://blog.rightscale.com/2011/05/02/aws-outage-follow-up-if-you-wanted-details-you-got-details
There is also a webinar that RightScale is putting on this week, May 6 at 11 AM Pacific Time:
Architecting for High Availability in the Cloud with Sr. RightScale Architect, Josep Blanquer
Register here: http://pages.rightscale.com/high_availability-050611.html
A "running history" of the Amazon Web Services outage can be followed by one of those hit by the outage:
http://blog.hootsuite.com/notes-on-todays-outage/