I've argued for a while that iTunes was the tip of Apple's sword. Being able to take payments and sell content in more countries than anyone else let them push the App Store farther, faster than any of their competition. Now, years later, no one else is even coming close, and when viewed as an ecosystem play, there still isn't any viable competition. To make matters worse, Apple's model allows them to sell the iPad (and soon, the iPad mini in 90+ countries. And, because they make their money off hardware, they can even sell it where there's still no or limited iTunes support. That lets them seed the market so hardware is in hand when iTunes eventually, and inevitably follows.
By contrast, Amazon's content appliance strategy with its heavily discounted hardware doesn't allow them to sell the Kindle Fire line in any country without an Amazon content store to subsidize it. They literally can't afford to. That means no seeding, and since Amazon has been nowhere nearly as successful as Apple in pushing their content store internationally, very limited distribution.
Here's why that matters...
