LOL, where the hell are you guys getting your numbers?
I gotta be honest, they're not reflected in reality.
Apple makes most of it's cash from iPhone sales, second from iPad sales, 3rd from PC sales, something like 3% of their cash flow is from the App store and iTunes.
The current margin on iPads is 31%, up from 30%, iPhones have about a 55% margin.
The App store and iTunes aren't a huge money generator, but they keep users in the ecosystem, the cheaper Apple devices are freaking gateway devices to the ecosystem, once you have one, it's very easy to justify purchasing more iDevices.
The margins on iPhones and iPads will decline as the industry matures and more competition forces the margins down, so Apple is great at getting cheaper devices out in volume by massaging the supply chain.
We're looking at 25% growth in the industry year over year for another 3 years or so, maybe 5.
an 8GB 10" iPad 2 at $349 will do a lot to spur other Apple products and upgrades for those that find the 8GB device too limited.
We'll likely see an 8" iPad soon, before Christmas to try to capture some of the Kindle/nook market, and serve as a gateway iDevice.