The only reason this won't be in the UK anytime soon is down to 2 points :
1) Greed of the banks. They don't want to give up any bit of money to Apple regardless of how small it is.
2) They're terrified of Apple getting a foothold into banking which could lead to them eventually being squeezed out and having less control of customer data which they rely on to market products and services to us.
If you want it in the UK go and tell your bank via Twitter, social media etc. and threaten to switch your bank account if they don't get it at launch.
Share everyone's frustrations and we could have it really really soon if only the banks weren't dragging their heels.
1 - you can say it's the banks greed, but it's also fair to say it's apples greed as well. In realty all the risk is put on the banks and not Apple. If i am subjected to fraud via Apple pay, it's it's not Apple who will be refunding my account and sorting out the problem. Also are Apple even involved in anything but simply uploading my details in the phone? Why should Apple get any fee at all then? That fee should already be built into the very high price we pay for our iPhones.