After watching the video from that link, I'm very fearful for what people are going to do with this technology in the next decade. This combined with Adobe's new "speech photoshop" will make excellent propaganda.
But now that I think about it, the most damage will come from making people even more incredulous... of everything.
It will become even harder to use evidence to prove a point. Uninformed people will just say "yeah sure, it's probably faked".
On the other hand... who could blame them?
Democratic institutions not only functioned but were put into effect before the advent of recorded or transmitted audio and video. Mass media has already been distorting the truth for over a century.
"Trust nothing you read online" becoming commonplace is something to be celebrated!
This is in fact happening, to everyone's benefit. Only in matters of vague mass policy (do we need giant walls? can markets sell health?) has it been largely corrupted by corporate propaganda. Which is probably not terribly worse than before. That scale has always been a big enough target to make it worth the effort to corrupt.
Right now, faking an interview via real-time 3d rendering plus capture of facial expressions would cost a ton of money. So anyone trying to do so would need (for e.g. to damage a competitor's reputation) both deep pockets and something valuable to gain from it (and would need to factorize the cost of getting caught, etc).
If this tech goes mainstream in the future, the cost would be so low that I can imagine some nasty things happening.
Hopefully there will be ways to detect this as this technique is further explored, so I'm not saying it's a "catastrophic development", but it certainly made me think more than just "oh wow, this is very neat!", which it also did by the way. It's incredible the kind of things researchers are able to achieve.
On the other hand, there's a difference between being doubtful something is real, and being aware that people speaking in public have an agenda, and a large portion will utilize half-truths and lies more often than not.
The difference between "the President lied about WMDs and got thousands killed over it", and "maybe the president didn't actually say that - archive footage might be false".
Just like (to pick a hopefully safely historical example) no president would record himself conspiring to perform illegal activities?
With such power, if all it takes is one douchebag to cause massive harm very quickly, then you should also believe it is possible for person to do massive good very quickly.
I'm not sure that applies for this technology. What massive good could be done by making a fake video of someone talking?