It will need to avoid the pitfalls of the previous technologies. (IR)
Audio, bluetooth, QR codes/camera as well.
All easily capable of data exchange between devices, all present on a vast number of phones, all hobbled by lack of implementation and standards.
Why wont NFC end up just like Bluetooth? "I don't have it switched on" "I don't have the same version" "we need to pair the devices? Mine says it cannot see any" "type in what code where?" "I can only support an NFC headset, not any data transfer protocols", etc.?