Indeed. The worst use of this will be forged political speeches. What happens when you can fake any video of anyone saying anything and then feed it to the social media outrage machine?
As the parent noted, society will adjust expectations about how to determine facts. When radio first came along, some people were fooled that Orson Welles's War of the Worlds [1] was actually happening, because it was in the style of a news broadcast. We learn and adjust how to process data as systems change around us.
You can already fake a political speech if you've got the resources. A look-alike and a good make-up artist can do a lot. The danger isn't a really good fake that can be discussed, but a high volume of OK fakes.
Its really not so different than it was prior to the advent of radio. By the time news reached you about what some politician said it had gone through multiple people and could be altered in any number of ways. Sometimes intentionally and sometimes through misunderstanding.
This is a basic assumption historians take. They assume sources have biases and agendas, and try to figure out what is true. It isn't a perfect system, but no historian takes a source at face value.
The question that concerns me more than Terminator- and Matrix-like scenarios is why we allow "the social media outrage machine" to exist in the first place. It is nothing more than a bunch of mostly uneducated opinions that create erratic views around the world of their M-sized subscriber sets.
Maybe this new tech will force people to bet their credibility on what they say and spread.
