Virtualization techniques and approaches

I began to compare some different approaches to virtualization available and to visualize them with graphical pictograms.

I am appreciating your feedback whether I achieved that goal or not.

The following articles are available so far:

1. Why virtualization?
2. Userspace-based virtualization (the easy way)
3. Xen: Hypervisor-based virtualization
4. ESX: Hypervisor-based virtualization
   
5. Solaris Zones: A sharing approach
   
6. Hybrid methods: KVM