Not content with making v2.0 of its OpenFeint platform available at WWDC last week, Aurora Feint has announced that it's supporting iPhone 3.0 features in the v2.1 beta from today.

Specifically, OpenFeint will now allow developers to use push notification for player-to-player challenges, taking on similar features in rival platforms like Scoreloop and ngmoco's new Plus+.

Meanwhile, the OpenFeint 2.1 beta also lets developers use microtransactions. Both new features are expected to make their way into games using OpenFeint by July.

The two new features will also work together, as shown by this example given by Aurora Feint (using its co-founders' names, natch):

"Danielle sends Jason a challenge using content purchased with Microtransactions. Jason clicks through the Push Notification and is prompted to purchase the content Danielle selected so he can play her challenge. With one click of a button, he purchases the content and jumps right into the game."

Those co-founders, Jason Citron and Danielle Cassley (pictured), are getting their hands dirty too.

"Danielle and I are personally planning on publishing a brand new game this summer using these features in innovative ways that will push the frontier of game development on the iPhone just as we did one year ago with Aurora Feint: The Beginning," says Citron.