Can Operating Systems be Replaced by Virtual Machine Software?

Coming out of VMworld, I've run into many people who've been convinced that operating systems are becoming an endangered species and that shortly they'll be replaced by virtual machine software. I believe that many have been convinced to adopt this position by VMware's powerful, integrated marketing not by the facts at hand. Let me address the facts.

• Hypervisors are small operating systems or components of general purpose operating systems, such as Windows, Unix or Linux. Replacing one with another doesn't mean that operating systems have gone away.
• Most applications have been written to use the facilities of an operating system and related system software. Until hypervisors offer all of those features, applications would have to be rewritten. Who's going to save money doing that?

I could go on and on but, I think that I've made my point.

What seems far more likely to me is that virtual machine software, and all of the other layers of virtualization technology that I've presented time and again in this forum, will take its place in the toolkit of a developer.

When appropriate, such as when the organization wants to consolidate applications from underutilized older machines onto a smaller number of newer machines, virtual machine software or a related technology, operating system virtualization/partioning software, will be deployed.

If high performance, scalability, agility or a unified management environment are needed, other tools will be brought in. In these cases, virtual machine software either isn't the right tool or needs help from another tool. Let's not be overwhelmed by a single suppliers marketing hype and be driven to make short term decisions that have negative long term effects.

Do you agree? How are you responding to the VMworld hype in your company?