> I do not think a huge number of payments are going to be made using it

First, this is an experiment and I'll be testing different permutations of cost, copy, and invasiveness.

Curious as to why you think there won't be much volume. Could you elaborate?

> I would totally pay with bitcoin, but refuse to sign up using any form of credit card.

This is an interesting data point. Was talking to a blogger about this project this morning and he asked why not use traditional payment methods. I presume (and hope) there might be more people out there like you than we all think.