I think MAC (Mandatory Access Control) applied to a desktop environment, picking a better language than C and actually thinking about stuff is more than sufficient to get around the existing problems...
Virtualization is just another pile of complexity and performance problems to deal with. It's not a magic bullet. Consider the following as well:
http://www.c0t0d0s0.org/archives/3651-Theo-de-Raadt-about-vi...
I really don't want this solution.
I'm sick of the lack of control over my data I have on android (not to mention iOS).