Check out this 30 page whitepaper from Gernot Heiser, PhD, CTO of Open Kernel Labs, Inc.  The introduction reads:

Virtualization has been a hot topic in the enterprise space for quite some time, but has recently become an important technology for embedded systems as well. It is therefore important for embedded-systems developers to understand the power and limitations of virtualization in this space, in order to understand what technology is suitable for their products.

This white paper presents an introduction to virtualization technology in general, and specifically discusses its application to embedded systems.

We explain the inherent differences between the enterprise-systems style of virtualization and virtualization as it applies to embedded systems. We explain the benefits of virtualization, especially with regard to supporting embedded systems composed of subsystems with widely varying properties and requirements, and with regard to security and IP protection.

We then discuss the limitations of plain virtualization approaches, specifically as it applies to embedded systems. These relate to the highly-integrated nature of embedded systems, and the particular security and reliability requirements. We present microkernels as a specific approach to virtualization, and explain why this approach is particularly suitable for embedded systems. We show how microkernels, especially Open Kernel’s OKL4  technology, overcome the limitations of plain virtualization.

We then provide a glimpse at the future of this technology.

Open Kernel Lab (OK) is a leading provider of embedded systems software and virtualization technology. Spun out from NICTA, Australia’s prestigious centre of excellence for information and communications technology, OK is focussed on driving the state of the art in embedded operating systems. OK’s technology aims at improving the reliability, safety and security of embedded devices.

OK believes that the best technology should have nothing to hide, and consequently distributes its code as open source. The company also believes that dramatic improvements in system reliability are possible in the near future, and to this end collaborates closely with NICTA and other research institutions on creating and commercialising the next generation of embedded operating-systems technology. For more information on OK and its products
visit http://www.ok-labs.com.

Download and read the whitepaper, here.