Our post is regarding IaaS clouds in general and has nothing specifically to do with EC2 or any other particular vendor. It may be the case that EC2 does have secure measures in place; I wonder how many of their customers can articulate them (or customers of other IaaS clouds for that matter)? We are merely raising an important issue. You can look at the many other posts we have on the other various aspects of security in the cloud of which this post forms the latest instalment regarding data storage.
"there are more efficient ways than encryption or "full sweep overwrite" to address this at the storage-level."
Your suggestion would be?
Kind regards,
Patrick