Google sees the mobile phone as a ubiquitous sensor network. You will be carrying with you, 24x7 (a recent study of Chinese mobile customers showed that the majority of them sleep within a meter of their phones), a very powerful, always connected, sensor-rich device. And the cool thing is, so will everyone else.
I wonder if the CALEA/key escrow ideas will be extended to a requirement that you keep a government backdoor running on your phone... Official Google Blog: The future of mobile | 
