I dunno. Hosting's cheap, and payment processors like Paypal and Google Checkout don't take anywhere near a 30% vig. Sure, at some point when you get big enough, you'll want to take CC transactions directly, but even then you're nowhere near 30%.

Comparing independent developers to enterprise resellers seems wrong to me. I'll grant that if you're *really* small, it's better to take 70% of a small pie with no overhead, and if you're *really* big, maybe the App Store is a bargain... But it seems to me anyone with monthly sales in the hundreds or maybe low thousands could probably keep more than 90% of their gross by doing it themselves, in which case we're back to how much the App Store is going to increase sales, and, frankly, I don't think the case has been made that it'll make up the difference for the average developer.