The retailers are going to find that their "loyal" customers are much more loyal to their iPhones and Android phones then they are to the retailer's brand.
Consumers like the loyalty programs because they are a benefit to them (lower prices without clipping coupons and points programs such as .10 off a gallon of gas for every $100 purchased in store). The consumer isn't interested in helping the retailer build a database about their habits for "targeted marketing". Most people if left to think about it, find the programs creepy and would actively use any alternative if it was just as convenient as having the little card on their keychain.
That's not even to mention the ridiculous amount of barriers CurrentC will have asking for people's bank accounts from the same retailers (Target, Home Depot, etc.) that lost their credit card information. At least with the credit cards the consumer is protected. Not so much with their checking accounts.
I wasn't aware anyone was using it yet. That's neat.
Stripe is a great example - after the initial card is created, everything is tokenized, and they only allow you to pull the last 4 digits as an identifier.
This was another decent teardown of Paydiant's Subway app - but it looks like someone high up has had some of the code redacted :) http://randywestergren.com/reverse-engineering-the-subway-an...
Functionally, it looks like CurrentC only has two advantages over *Pays - loyalty integration and big box retailer backing. Not likely enough, but will be interesting to see how it plays out in the lower end market where a flagship device is not required...