When we toured iPhone 3.0’s best features, we mentioned we hadn’t yet seen many applications that supported push notifications. Now one of the big ones—AIM—does, delivering instant background messages even when it’s not running.

As a refresher, Apple doesn’t allow the iPhone to run background applications. As a workaround, the new iPhone 3.0 supports push notifications that send SMS-like alerts straight to your phone even when an application isn’t running. That means that you get the benefits of background apps with none of the battery drain.

Based on comments on other blogs, overall the push notifications seem to be working really well for this program. No notifications were coming through when they was still actively logged into AIM through the desktop client, but once signed off at my desktop, the push notifications started making their way to the iPhone. It’s a kludge, but a useful one.

As with all apps supporting push notifications, you have the option to toggle the in-your-face level of the notifications, selectively enabling sounds, alerts, and badges. If you’ve been playing with AIM or other push notification-supporting apps since the 3.0 update, let’s hear how it’s been working for you in the comments.