I hope this is expanded beyond the US. I would get in a heartbeat; if Apple can expand this offering to Europe and other parts of the world with very little use of credit cards they will be able to create new business at a massive scale.
The problem is credit card business in US is a)much more profitable due to significantly higher interchange fees and b)credit cards adoption is much higher.
Credit cards would be more popular in Europe if they offered any significant benefit at all.