I've had three bad experiences with Lumia, and it has been enough to think about a move, and since I've done Symbian, Blackberry, Android and Windows phone I may consider the iPhone 6. I'd have to see and play with it to test the water, and since there are some decent Windows Phone and Android options coming up it will make it interesting.
So...bring them on...
c
Go for it, or just try out iOS on a non-contract device such as their iPod Touches. You'll have access to a lot of apps - way more than you know what to do with, but at the end of the day you may find the UI cumbersome. Once you've used WP's UI with Live Tiles, everything else just seems so... I dunno, meh?
The way I understand NFC payment, it basically sends your payment information, which is what the magnetic stripe on your credit card does. Some credit cards actually have this functionality. I don't see how Apple Pay itself is so important. The vendors need to have NFC terminals. Google Wallet has been doing for a long time what Apple Pay will do.
With the Apple payment, your credit card number does not stay static. That's pretty good security there in my opinion, and is one of the key features of how it works on their device.