That said, the article is kind of lame. It assumes that a growing economy translates directly to a skilled labor shortage without making any decent case for that. Really, it's only even in passing that they make a case for moving there.
I know many people from the USA who work here in Bangalore for a year or two and then go back to the USA. As I understand it the paperwork for the work visa is a little tedious, but hey then getting an H! involves a lot of paperwork too. Ideally you get a job first and let the company take care of the paperwork for you.
As for the continents themselves, it just depends on who's doing the teaching. English speaking countries define North and South America as separate continents:
The bit I was digging into there, by inference (not necessarily clear for those not familiar with Spanish) is that because North and South America are taught to be one continent in Spanish, and "americano" references the peoples from that aggregate, Spanish speakers (mostly Latin-Americans) have a habit of correcting English speakers in online forms when they use the word "American" to refer to people from the US.