Everything changes. Some changes are slower, some are almost instant. If you want to be a university professor because you want to get paid to do research, then become a great researcher and it is very likely that you will be able to find a place in academia. If you want to teach, things MIGHT be different. Ten years is a long time, but large structures like the university system can be slow to change. Even if Khan style teaching takes off, it will take a significant amount of time to get enough lectures for everything together.
I am a math teacher, so I think about these kinds of things too. However, instead of thinking about how I might lose my job, I'm trying to think about how to most effectively help the largest number of students. To find a way to reach students that others can't reach. To think of a way to better engage students. To make learning math more fun, or faster or more effective. I love teaching, and I will continue to do it, though I realize the way I do it WILL change.