AND, to mention something important that is related to the world cup:
road safety.
To help keep the fans safe in Japan please be aware of a couple of basic points:
1. In the UK most cars stop to let you cross on 'zebra crossings' (the road crossings with black and white stripes and no traffic lights) - but in Japan most cars don't stop. Normally several cars will go through before one stops to let you cross, even if you are clearly standing there waiting. As fans coming from one of the four UK nations wont know that it could lead to some accidents. So watch out for that please rugby fans.
2. In the UK cars can not turn into and drive through the normal pedestrians crossings (the ones that do have green go and red stop signs) when it's green and people are crossing. But in Japan they can and do - legally. And many times they do so very close to the people walking and at some speed. So watch out for that too, and be careful crossing.
In other ways, of course, Japan is a very safe country.