Fixed.
For right now, right at this moment, this is a Sprint-only application. Like I said, it is not on any other phone in the US, Nexus or otherwise. You can buy an unlocked, unbranded, Nexus S and you won't be able to use it without rooting and hacking it on there. You can buy the Nexus S direct from Best Buy, in the United States, unlocked, or subsidized on ATT, whichever you prefer, and you won't be getting Google Wallet.
What everyone is expecting is tantamount to someone expecting that you are going to be able to get VZW Navigator on a T-Mobile phone, because T-Mobile doesn't have the authority to block it so you should be able to use it. Wrong.
When Google Wallet came out, Google explicitly stated, this functionality is available on the Nexus S 4G from Sprint. And they left it at that. Nowhere did they say this will work for any other device. Google has also not announced that it will work on the Galaxy Nexus whatsoever.