I do believe that having more information will allow for a more accurate analysis of why people behave the way they do, that is, their motivations.
However, I am not sure that all of the observable facts in the universe about an individual will be sufficient to completely predict motivation and behavior. People are complicated - the older I get, the more introspective I get, the more I pick at and analyze and assess my own actions, the more frequently I find that I do not have clear reasons for what I do - and I learn things about myself. If I have trouble figuring out why I do what I do, how could an outsider - one who does not possess the same set of biases that I have developed myself, via my own life, choices, experiments and education - ever hope to understand me so well as to correctly declare my motivations and predict my future behavior?
But then, to restate my first claim, more information will yield better accuracy. But can everything the NSA, or google, collect about me ever be enough?
Surveillance as a topic overall is interesting because it is so resistant to black-and-white rule setting - context is everything. Now I have something to think about on my afternoon walk.