I’ve submitted a new app to the App Store called XForm. You can read more about the app here. The app will only run on iOS 4, since it uses the new iAds framework. The model Apple is putting forward is simple, and since my company is already set up for payment with Apple, it just piggybacks on that.
What I like about iAds is that Apple pays for impressions, not just clicks. From what I can find out (AdMob’s site hides the details on this pretty effectively), AdMob only pays per click, so you get nothing for showing the ads. The other element of iAds that appeals to me is that the user never really leaves your app: the ad is displayed when they tap on the ad as if it was another panel in your app. When the user closes the ad panel, they are returned to your app in whatever state it was in at the time. Many of the other ad banners on the iPhone take you out of the app and into Safari. This means the user now has to go back to your app (either via the Springboard or via the new app switcher in iOS 4). The iAds approach is quite seamless.
Of course, until iOS 4 goes out and people upgrade, I won’t see much in the way of usage or sales. All of this also presumes Apple will approve the app for sale :-).