>If bitcoin succeeds, credit mechanisms will be built on top of it, and they'll behave almost identically to credit cards, including have fraud.
Why? One way transactions cut down fraud. It's not inconceivable to have a hardware digital currency wallet that can be used similar to the modern credit card. Banks could issue credit that is spendable in the same way with additional automatic escrow. Why continue to have the fraud ridden system when the alternative exists?