[moffkalast]

> No company like a Amazon or Visa has a clear picture of what those transactions are about.

That's where you're probably wrong. If the NSA can listen to anyone on the planet through their phone, they surely have the data that exchanges are legally obligated to collect in terms of validating all users by their government documents, aka the place 99% of bitcoin users probably get their coin.

The rest is just mapping it all together and correlating the remaining blank accounts with the piles of other data they've got on each person, which I'm sure they're easily capable of. A bitcoin transaction and a book download coming from a the same IP at roughly the same time are surely mappable to a physical person.