Amazon's Kindle business is interesting to me due to their internal team structure. They have the Kindle hardware team responsible for these units, then a second independent team that does all the software versions for the iOS, Android, Windows/Mac and so on. So on the hardware side, you have Amazon going after Apple's iPad. On the software side, they are adding value to the platform the hardware side is targeting by releasing Kindle for iPad. Really interesting way to hedge your bets either way.

By doing it this way, they may pull people into the hardware side based on being on the iPad in software form. $99 (or even cheeper) gets to the point where people justify one alongside the iPad. Reading outside? Kindle time. Reading at night in bed? iPad time.