I live in China these days, they tried NFC Sims for the Expo. From what I heard the system fell down on day1. So, if you wanted lunch you had to go join a large queue to buy a credit card sized NFC, then after lunch you had to join another big queue to get a refund of the money that was left - why ? because you were only at the expo 1 day and NO-ONE would accept cash for lunch and the card only came in 1 denomination!
I would also suggest the rate of phone loss / theft would make it impractical because the sim needs replacing, then 20 screens of authorisations to get the account transferred to a new sim card etc.
If you lose your phone how are you going to call to get the NFC function blocked before someone buys 5,000 packs of cigarettes on your tab ?
Also, I'm not sure it would work in my current phone, the sim is buried so deep underneath the battery it's probably an effective shield :)
I have an "nfc" transport card, SPTCC, it works in Taxi's, Buses, Ferries and some trains. I can top it up in a metro station or a local supermarket (24*7). It's durable, solid and won't blast me with adverts every time I use it.
That's the final straw with anything for me, if you keep pushing adverts in my face then yours is the first service I dump.
Wise up guys, NFC could be nice, just keep the Ads out of it.
Oh, by the way, don't tie me to one country, I travel, and when I travel I want to use my NFC to get a coffee anywhere that "nfc" is available, Thanks...