Apple may eventually end up selling 20 million iPhones worldwide every year. It will be faced with the unpleasant reality that now bedevils firms like Motorola and Nokia. Sales volume is not any good as a substitute for a high yield on each product. Low margins have never been part of the Apple formula for success.
Apple hasn’t switched to low margins for the iPhone 3G. They’ve switched from taking a cut of the monthly service fees to an up-front subsidy from the carriers.