Machines are good at making the same thing over and over again with very low variation in specification. Machine lathes, auto parts, plastics, etc.
However, machines to do these things are VERY expensive, so they have to be able to mass produce a lot of parts.
Machines have a much more difficult time with tasks like assembling parts, primarily because logic has to be programmed (that humans already have) to figure out the direction and position of a bolt on a belt, for example. There are machines capable of this kind of activity, but they are even more expensive than the machines that make the same part over and over again.
I think Saturn has machines that weld and assemble cars.
The part that scares me in the near term is that fact that humans have almost completely been removed from decision-making processes, like credit.
I helped automate a major West coast bank's loan system. The system took an electronic loan application, went and collected information from about 5 different systems (prior banking history, credit scores, etc.), then sent the whole XML bundle to a company that then basically made the credit decision.
Now, imagine if the Department of Homeland Security did the same. Now, imagine that someone who didn't like you decided to report an erroneous event on you that you were a terrorist. The system would probably report your every credit card transaction, when you gassed up your car, and all your air travel. It really would be 1984.
I read an article in Wired or FastCompany or some magazine like that a few years ago about a man who was experimenting with chip implantation (in the body). My fear is that the Dept. of Homeland Security might eventually require such a thing (under the guise of reducing medical records costs), then be able to track every person in America, within a few feet.
That kind of thinking makes me want to flee to some remote part of the world, buy only in cash, and have a different name.