Lots of debate here on what is more powerful, the data or the metadata. I think in the case of voice content, a case can be made that the metadata is more power

Lots of debate here on what is more powerful, the data or the metadata. I think in the case of voice content, a case can be made that the metadata is more powerful, simply because it's already parsed into a quantitative, objective format that's relatively easy to analyze en masse and find "suspicious" patterns within the public. With voice content, I don't think our natural language processing chops are up to par to deal with the massive amount of data and connect the dots in meaningful ways. Of course, if you're already targeting a specific individual, and you can get a human to listen to the voice content, the debate is academic - both kinds of data compliment each other and are equally powerful. Metadata still acts as a better "gateway drug" for narrowing down individuals though.