I don't see why people are so worried about iAd. How users respond to it will keep it in balance. As long as people don't want it to be in paid apps, reviews and people buying other, ad-free apps will make sure that iAd stays in free apps.
And really, this makes ads better for the user, too. I might actually tap on some more interesting ads now that it won't take me out of the app and into Safari.
There is no way you'll be able to disable ads or else there would be no point in having them. 😛