For what it's worth, Google has extremely good public transport data for Perth, Australia, and it worked quite well for bus & train times when I was in Sweden l

For what it's worth, Google has extremely good public transport data for Perth, Australia, and it worked quite well for bus & train times when I was in Sweden last year (especially Malmö). So it's not just the US. Google's support probably depends in part on the transport authority providing a timely & accurate data feed of their schedules that Google can use.