My first exposure to virtual machines was in the late 80's on a IBM mainframe (running VM). At the time I really had no idea how they worked. I did know that I could write programs that might "crash" horribly but would not effect other users of the mainframe (there might be hundreds).

When I discovered in the late 90's that I could get a virtualization product that ran on my PC I was pretty interested. I purchased VMWare Workstation and used it to run Linux virtual machines under Windows (a great way to test and develop).

Virtualization does not eradicate complexity and as complexity moves, corporate IT departments need to ensure storage technologies keep pace with similar progress in server virtualization.

VMware's popularity belies its complexity

My primary interest in virtual machines today is related to distribution of virtual appliances. Virtual appliances will make it feasable to package complete "stacks" (e.g Apache, MySQL, PHP, and custom logic) of products as a single virtual machine. Organization will be able to run this virtual appliance on a server (along with other virtual machines on the same physical server) without having to build or install this software on the server...they will simply install the virtual appliance.