That's actually the more disturbing part about this: it require computational resources that only governments and large corporations can afford, so they are the ones who gain the most from it; and it gives them more leverage over the population.
And it doesn't look like the NSA for example is doing anything useful from its own perspective with the data they actually have...
All the data everyone is feeding into FB/G+/Twitter/etc about their friends and acquaintances could not have been collected on such a mass scale by the NSA alone.
If you're a privacy conscious individual, there's definitely reasons to be fearful of this approach to surveillance by any governmental intelligence agency.