FWIW, my email to Amazon (about losing my business) resulted in the boilerplate reply with a link to the complaint form.

I agree and I am disgusted by Amazon's lack of cogent response. I just wrote to them about losing my business. Since I use AWS and have been purchasing from Amazon since they started, this is no joke, but it will take more than one customer doing this to make them wake up. Please keep posting on the web if you are convinced that they should be proactive in resolving the attacks quickly. This is NOT comparable to spammers abuse. In one case, 200 register requests per second were being received. Yes, you can drop packets but your connection itself is still being hit at that level. Best case, your upstream might drop the packets. This would actually be a business plan for someone: guaranteed packet filtering before your own connection. In that case, you only need to enter an IP or range, and you'd never see that IP again. Unfortunately, it isn't that simple with some of these attacks, I I guess EC2 makes them easier to perform, which is a part of my complaint. Keep hammering until this is resolved! It's legitimate to complain about their lack of reaction.

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