This is true, but for the vast majority of consumers would supporting a trusted block of javascript be good enough? All the movie industry wants is to make sure that Joe Sixpack cant get a digital copy of the data stream.

I know I am sortof commandeering the word "trusted" for something much weaker than what I think industry wants it to be here, I realize that. Maybe using such a term in a weak solution would satisfy the pointy haired bosses of the world. >:)

Seems to me if some rogue binary goes in and tampers with my Firefox or Chrome binary in order to circumvent browser security, then the browsers would know it and fail with an error. Obviously, any browser that builds from source can be directly modified by a developer.