Software licensing fees make a big difference in this realm. Embedded systems simply can not crash. Embedded systems generally have to be small and cheap. Whatever operating system runs on them must be able to make good use of low-power hardware. Every embedded application will be different, and will require the ability to customize the system to the environment.
Source is power.
Linux looks like a real winner in the embedded environment. It nicely satisfies the requirements of such applications, while simultaneously providing a great deal of power to developers. I would like to thank Paolo Marini for providing so much information that this article almost entirely wrote itself. Any errors in translation from Italian are entirely the author's fault. Eklektix, Inc. all rights reserved.