I sent Amazon a message today asking if/when they'd start taking bitcoin as payment, and mentioned bitpay as an option that's even cheaper than credit card merchant fees. Here's what they sent me:
If you can take the time, please go to your amazon account some time this week and send a question in about bitcoin. Obviously they are reading their mail. The best way to get them to take it seriously is to have the customer base asking about it. Cheers.