The NSA doesn't care that your grandma fell in the garden and twisted her ankle

[Robb]

2. As an intellectual exercise, I've been thinking about it in terms of Google Analytics.

Google collects data on every single search -- organizes it in part by IP address, as I understand it. And the data just sit there until patterns are queried, at which point it sifts through what it has, not in real-time by any means, and not specific to User A or User B, but rather the actual useful-to-business patterns of "77% of users searched for X, found Y on this page then clicked on the following links."

That sort of information is what's most useful to businesses, because they can fashion their websites to take advantage of those patterns.

I expect NSA has its own set of needs, has decided what patterns of information are most useful to its intelligence requirements and builds something quite different, of course.