um... in what way does it hurt more?

That was a stupid comment made in haste that makes no sense as written. Paying apple 30% of repeated micropayments would hurt me more than the alternative, but it's only true in my context - which is probably not the context Apple designed their system for.

I am building a web based service which can also be accessed via an iPhone app. I get paid via micropayments which I aggregate till they reach a certain dollar amount and then process via a payment processor that charges me in single digit percentages. I have the option of using iPhone's own micropayment service but that would hurt me more.

The advantage of using the app store micropayments is that users don't have to create a new account somewhere and put their account info in your app. They can use an existing system and have a one-click buy option.

It'd be interesting to see what will result in more profits. My guess would be that the increased sales on the iPhone outweigh the higher profit margin with the alternatives. This depends on your costs too of course (e.g. copyright fees for eBooks)

Thanks for the decent response.

So for payments received from other sources (non iPhone), you get the full amount, but if you were to make use of the new micropayments in OS 3,0, you'd be down 30%? I can see how that would hurt