The rule of thumb for switching out a human for a robot is twice the human’s annual salary. Since new-generation robots such as Baxter and its kind ( others are soon to arrive from Universal Robotics, ABB, FANUC and Yaskawa) run about $20K each, the business decision is easy to enough to see.
It’s said that $500B of the US GDP’s total output of $15T (2011) could, in the near future, be thrown on the backs of robots and that these machines at critical mass could make offshoring of US manufacturing a distant memory real fast.