As we mentioned yesterday, Apple has begun load testing of their Push Notification Service. Certain developers have been given promo codes to a special version of AP News that, when installed, can be configured to utilize Push Notification. This means that screens we've seen previously via code digging can now be seen for real, and there are a few interesting things therein.
The setup seems not dissimilar to how GPS was handled on the iPhone 3G. A popup identifies the app and requests permission to send you Push Notifications, and you can choose "Don't Allow" or "OK". A Notifications panel in Settings lets you choose to globally turn the service On or Off, and lists the apps using the service so you can individually toggle Sounds, Alerts, and Badges On or Off as well for each one. (i.e. if you want Twitter to badge but not alert, IM to sound but not badge, etc. you can have it your way).
More screenshots after the jump, and check out our massive iPhone 3.0 Walkthrough for even more!