Any chance the in-app purchase will be implemented?

In-app purchase is supported on the Blackberry Playbook: http://renaun.com/blog/2011/01/using-blackberry-paymentservice-with-ad obe-air-for-the-playbook/

In-app  purchase on iOS and ANdroid should be supported in a future release,  either directly or through the extension API we are working on. On  Android, you can create a hybrid AIR/Java app (see http://www.jamesward.com/2011/05/11/extending-air-for-android/?replyto com=163323), although that isn't officially supported. I haven't heard of someone doing anything similar on iOS.