Top 5 from Tokyo, London, Sydney, and "the Tube". I'm wondering is it because people outside of US tends to use twitter to stay contact with friends and family more or yc has gone global.
This is possibly because we started our index crawling from one Australian (who lived in the UK for a bit) and one Chinese person so there is most likely a bias towards AU, UK and HK at this early stage of our crawling. As we hit a more critical mass this will even out and most likely become a typical US weighted result in Twitter.