None of them accept electronic payments and tie that to your a personal credit card or checking account....
No wait, that is exactly what they do.....
Google adds near field and Apple add some electronic ticketing stuff.....big deal....
I guess you really don't know what the iPhone Passbook does. It does not "accept electronic payments and tie that to your personal credit card." That's the Google Wallet, yes. Passbook collects all passes, coupons, offers, and other similar pieces of data, and makes it available form a single place. It then can issue automatic notifications at the appropriate time or place, based on the context of the document. However, the documents themselves are generated by their individual apps.
Passbook offers developers an interface to "add" these documents to the common container, but the individual, third-party apps are responsible for the offers, payments, or any other function. It is not so much an electronic payment system, rather a "smart" wallet that holds your cards issued by third parties.
For instance, you want to pay at Starbucks using Passbook? You need to get the Starbucks app, log into it and enter your credit card details. From then on, the app can generate vouchers for offers or discounts (while in communication with the Starbucks servers)--and *those* can then be put into the Passbook.
It puts third party developers retailers or service providers in control of the payment or coupon mechanisms.
That is absolutely orthogonal to Google Wallet. It is, however, identical to what Samsung Wallet does. Get it now?