What? I feel like some information got crossed. Just like with any of my cc or debit cards I still put in a zip or pin. Why would software gimp just the transfer of a card number through NFC? You mentioned a secure sim, are carriers nixing this?
This post is from a while ago, but since someone bumped it for another reason... basically a NFC payment system requires a secure element for credit card cryptographic information to be stored on. On Android phones with Google Wallet, that secure element is inside of the phone. Microsoft instead decided to have the secure element on the SIM card, probably because they don't have the clout of Google here, and the carriers prefer secure SIM because then they're a part of the payment process. In some ways though, the secure SIM makes more sense, because then switching your Wallet transactions from one device to another is just as easy as switching your SIM card.
That being said, no carriers to my knowledge have gotten anything off the ground in this area yet. Secure SIMs exist, but there isn't anything to use it for. Microsoft promised that they would have something in place in the US in 2013, but there hasn't been any further news on this yet.
And yes, I agree that Wallet is near useless even still.