Not only all that, but there's been a lot of evidence over the past couple of decades that the rate of innovation per capita goes up with density. Density brings more people into contact more frequently, which leads to more innovation, more economic growth and more employment.
When I was a boy, twenty years ago I firmly believed that I would need to move to London as soon as I could, just for the British library and access to information. Then the internet happened (well the web, and it was already happening but for me, that's when it happened). The internet made distance so much less of a factor, and i suspect that this trend will only continue. I suspect the density/creativity association will break down, but I have no evidence either way, so I could be completely wrong.