I remember reading something about authenticating when you put it on via phone, somehow, and then if you take the watch off it'll require re-authentication. Don't quote me, I can't find the link. But I didn't dream that.
Perhaps I've missed it, but can anyone confirm if any bank card will work if it's a Visa credit/debit card, for example? I have to assume it will, but then I look at the banks that have signed up and I'm unsure.
Seems to reason that my personal bank card, with the Visa logo, would be able to be added to Apple Pay/Passbook.