Interesting. Now I'd like to see a CPU benchmark, but I imagine that would be influenced heavily by who else is on your machine.
There have been a ton of cloud CPU benchmarks, e.g. http://cloudharmony.com/benchmarks If the cloud is implemented properly there should be minimal interference from neighbors, but it would be an interesting thing to check.
Those benchmarks are for S3, not EBS.
I'm sorry, I don't have experience with the Amazon cloud, I don't know what EBS is :)