20-Year Prospect
As long as a need exists for there to be a skilled negotiator between the skilled people and those skilled with cash, talent agents will always find a job. With over 11,000 jobs in this high turn-around industry, there are lots of opportunities available and there's no reason for that to change (source).
In fact, with the American movie industry growing into global markets it has barely even touched in the past, the biggest changes in your job may be where you do your work. China really likes American movies and Hollywood producers are more than happy to send productions overseas to film actual Chinese epics in China.
It may seem strange to film American movies in China—until you realize that there are over a billion prospective ticket buyers who appreciate getting settings right just as much as you do (source).
We're just saying learning some Mandarin is probably a good idea.