Push Notifications on iPhone

Apple called registered Developers to test the Push Notification Services. The test App was AP News and the test has a limit of one week.

Here is the original Mail from Apple (Source: MobileCrunch)

As a developer actively working with iPhone OS 3.0 beta, we would like your help in testing the Apple Push Notification service. We have selected a pre-release version of the Associated Press app for iPhone OS 3.0 to create a high-volume test environment for our servers.
To participate, we ask that you follow these steps:
Download the pre-release version of the Associated Press app for iPhone OS 3.0 from the iTunes Store via your desktop by entering this unique redemption code in the ‘Redeem’ section of iTunes, found under the ‘Quick Links’ section:
This unique redemption code and the functionality of the application will expire in seven days.
Install the application on a development device running iPhone OS 3.0 beta 5 by synching it to iTunes. Make sure to accept notifications when prompted after installation. This application can only be installed on devices running iPhone OS 3.0 beta 5.
When you first run the app, choose U.S. English as your region when prompted. The U.S. English region will receive alerts, the Canadian English region will not. For purposes of the test, AP will be sending a high-volume of real news alerts.
If you do not receive notifications from the app within 48 hours after installation, let us know.

I think Push Notifications would be a great improvement for iPhone Applications. Instant Messaging or Social Network apps like Twitter and Facebook would be much more intuitiv. When this technique works without problems, background processes would be redundant at all.