I dream of a world where a web of trust signatures are taken seriously. A few hops should get you to a real human holding the camera who claims it's a real recording. If that person or someone along the way is regularly flagged as malicious by others that you trust, you can blacklist them.

I think the terminal solution to this, in the US and maybe the EU, will be putting identifying code/chips into all devices capable of connecting to the Internet that will tag all content (video, text, audio, images) in some way where browsers will have to legally change to interpret them. This will make everyone either unable to use the Internet or known to anyone that "needs to know".