For those in the US, a googly is a way of delivering (pitching) a ball in Cricket. The American equivalent terminology would be 'throwing a curveball'
Of course, I assumed that American football would be right up there : Turns out, it's a minority thing, by a long way.
(in america => does not know cricket) <=> (knows cricket => not in america)
(I've had a few random conversations with Indians while travelling recently, and they knew more about the players and results in domestic leagues in my own country than I do)
If he starts with "For those in the US", he's assuming that the rest of the world knows about it. Rest of the world != Commonwealth countries.