I've just joined Udacity to get some online education. On having a look around the community discussion boards it quickly became evident that the main traction for conversation (or statements of opinion) was where other members of the community are from. By quite a significant amount.
I also went past a chap in Trafalgar Square the other day who'd drawn up all the world flags in chalk and was encouraging the square's many international tourists to place coins on their home countries flag. He was making a killing both in crowd engagement and financially.
Seems that we'll always have a deep rooted sense of ties to our homes, and interest in others own origins. So if you ever need to get a discussion board going just ask were everyone is from.