there are several reasons why you may want to run virtual machines on one lump of hardware, be that a server, desktop, laptop, or mobile.

a) apps which are not available for that os
b) apps which do not coexist, or for having different versions for testing and development purposes
c) sandboxing for say bittorrrents so that services or hosts are not exposed needlessly.
d) assurance. a specific example here is secure access to corporate email which is an issue where i work. i could have a secure vm on my mobile device in the future, whereas now i have seperate devices.

I think virtualisation will take off in the mobile world for specific areas such as security compliance, i think app virtualisation will the big area though for the mass consumer market. so that apps for one platform can be ran on another. that may be via cloud based services though

one more thing, vmware is a business, but a lot of their products are available to use free for basic use, which can then be used as a foot in the door. that could well happen if they see an oppurtunity here, which they seem to have not done so yet.