I've downloaded a few Passbook apps from the store but they just get their own icon on my home screen. They don't get put into Passbook. Am I supposed to drag them onto the passbook icon?
A pass is just a file that lives in Apple Passbook app. The Passbook app sole and only purpose is to have a single place to store all your passes. Your Passbook apps are just apps that happen to interact with your passes. This is not like the newstand folder when a very specific class of app are displayed in this very specific folder and no other apps can be displayed here and the apps can not be displayed elsewhere. The Passbook app is not a folder: it is an app that contain data.
Passes can be created in 3 ways:
- received by mail
- downloaded from a website
- created by a Passbook app
So a service provider does no need to edit and distribute an app to use Passbook. Your email address or visiting a website are enough.
Passbook apps are apps that are able to create, edit or delete passes. An app can access only passes signed with the same vendor code : your Starbuck app can not access the passes from Delta Airlines. Previously, the app was the way you interacted with the service provider before Passbook. Your Starbuck app would allow quick payments and your Delta Airlines app would contain your tickets. Now those apps allow to store those items in Passbook as an alternative. The added value for the user is the fact that all his tickets/cards are at the same place, support push updates and geoloc activation (passes can have geoloc information so they conveniently popup when you are near a Starbuck or approaching the airport).
Passes are just static data but they have specials trick to allow some kind of dynamic content. When a pass is stored in the Passbook app, it can (if configured) call home and register the device to receive updates for this pass. So if the service provider wants to update the pass (with a new account balance, updated boarding information, etc ...), they can push it.
This is all you should now to properly handle your passes and understand what's possible and what's not.
NFC is completely unrelated to Passbook. NFC is a near-field transmission technology, with only a few normalized usages (like BlueTooth but with much less profiles and existing devices). Passbook is a software solution aimed at solution real-world situation. Passes being static data, a complementary usage between NFC and Passbook would be to beam the content (or part of) of the pass to a nearby device. Passbook does not require NFC to perform the same usage: it can display a 2D code bar that can be scanned by devices that are already deployed today, providing added value now. And here NFC does not add any value, just an alternate technology.