I was just talking with someone about this yesterday. I think it's very likely that one out of five jobs will be replaced by automation.
There will be opportunities and other jobs created... but the transition will not be a smooth one and the people who are out of work are not likely to be qualified for many of those newly created positions.
I see this as very problematic for the United States, as we've depending so much on "middle class" economy. It may be better in developing countries as they may be able to grow into a new economy more easily and eagerly.
Hard to predict what will happen... but that won't keep us from trying!