[jonhendry]

Amazon has already demonstrated a willingness to develop and release kindle software on 'competing' platforms. Even the iPad, which some consider a direct challenger of the kindle.

Should Amazon decide to exit the hardware space, there would still be the kindle software for other platforms.

The difference between Amazon and Walmart is that Walmart's music service was far from their core business. Amazon's business is to sell things, especially books, online. That's why they don't limit their ebooks to the kindle device. They don't care if you're using an iPad or a Blackberry, so long as you're buying some of your books from Amazon.

Walmart's core business is to sell things in stores. I'm not sure what value an online music store really gives them, so I'm not surprised they killed it.