Consumerium Credit
This is one of several controversial visions deserving more exploration as some may conclude they are actually best cases and worth effort to pursue.
Consumerium Credit is an evolved Consumerium Buying Network based perhaps on the Consumerium social club (call it Consumerium Buying Club for now) where everyone participating has a Consumerium checker that actually provides direct access to the medium of exchange used to pay.
Basically, you walk into the store with only this one device, receive all the Consumerium buying signals you want, obey some, ignore others, and either way when you want to buy, you just "click buy" and the transaction is done. You can walk out the store without even stopping at the checkout, and if anyone stops you they can do a spot audit to ensure everything is checked - if you doubt you actually swiped everything, go to the checkout counter as usual, but the payment will still be processed via the Consumerium Credit system.
This arrangement could set a standard for electronic payment services or could just replace them - that is, you could actually be invoking one or more debit cards or credit cards or a net-based scheme like PayPal, or, most radically, paying directly via some bank Consumerium has contracted for this purpose, and in which you deposit some of your money.
Advantages of this scheme are significant: user data is much more accurate, individual buying criteria are monitored directly and user data adjusted, institutional buying criteria can be directly enforced (you simply can't buy what doesn't pass), and such systems as RFID more or less could be made to work with low privacy risk (you already trust Consumerium, so no extra trust is required...) for our users.