Of course that's what they are thinking. But that line of thinking is brittle in a couple of ways: With no constituency for applications on an Android runtime inside of Microsoft, there will be a tendency to find "synergy" and make products for Windows Phone first. Windows Phone has a small enough share that it could fall off the bottom of the mobile market share ladder. Even without a complete market failure, the natural tendency to serve an internal constituency first and best will limit the reach of Microsoft's ecosystem.

There is a good case to be made that Amazon is a better competitor against Google's media products because Amazon's native platform is based on AOSP and development uses the Android toolchain.