What Will Happen When U.S. Wages Converge With China's?

This is from a venture capitalist's blog post on outsourcing vs offshoring:

On the plus side, offshoring often offers considerable cost savings. Labor costs in emerging markets are often a fraction of the labor costs in the developed world. And you can often tap into highly educated and skilled labor pools. We have companies in our portfolio that have built world class engineering teams in places like Belarus, Solvenia, and India. These teams cost less and often produce amazing work. AVC community member Ken Berger has been involved in building a strong team of ruby engineers in Vietnam. I have no doubt that team can do excellent work at a fraction of the cost of a team of ruby engineers in San Francisco or New York.

So... what is going to happen to the ruby engineers in San Francisco or New York?

What is going to happen to San Francisco and New York when the wages of their ruby engineers converge with Vietnamese wages?