I went through the process, just to evaluate it.

I couldn't see how to pay as checkout part 1/2 said Google Checkout.  But then after submitting that I see part 2/2 which lets you choose Bitcoin as the payment method.

In response is:

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Your Order ID is: #nnnn

Instructions for Bitcoins (Btc)

Thanks for using the new way to pay on the Internet! We will be emailing you with the final total/payment address of your order in BTC based on the current USD exchange rate.

If you have any questions, simply contact us via email at babbletees@gmail.com, or phone at 815-780-1953.

Thanks for using Bitcoins!

An email receipt containing information about your order will soon follow. Please keep it for your records.

Thank you for shopping at Babbletees.

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Eventually we'll start seeing ecommerce sites able to build in the bitcoin payment handling, but even this method works for now.  Thanks for adding bitcoin as one of the methods!