They're straight-up refusing to talk to Jason about giving Archive Team a data dump. There's an ugly situation, but only one side is precipitating it.
Edit: On second thought, I agree that it's probably related to the bandwidth cost.
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I wonder if the Archive Team has considered sending twitpic a hard drive and asking them to just rsync the data over?
Edit: This assumes that they keep backups of said data outside of EC2. Walking a hard drive over to your local Amazon DC.. won't quite work.