However, I decided to run an additional experiment to contact Amazon since the IP was originating from an EC2 instance. Amazon contacted me after I filed an abuse report and said they were investigating.
A week goes by and I'm still getting hammered. So I email Amazon and asked when it will be resolved. No response. So I email again, again, and again. I finally get a response saying they have resolved it, but I'm still getting hammered from the same IP address.
So I email them once more asking - what is it exactly you have resolved?
No response.
I presume it is not in Amazon's best interest to resolve such issues as long as people are paying for their instances....