I've had a few experiences in small Japan chats, where it's fun talking with people. There may be one Japanese person there, or none, but usually there are people from all over the world there. Which is ok cos I like speaking with everybody. There are only 2 kind of people I like - Japanese people, and gaijin people. (gaijin meaning to me anyone not Japanese which is the wrong definition I'm sure and not "foreigners in Japan" which is probably correct).
However most of my experiences in chats have been pretty lousy. Esp. in the big ones where people pop in & out looking for someone, people are often rude or the conversation is too hard to follow. Smaller ones it seems the people are nicer. What would be good would be to schedule a chat and you can announce, for a certain time. And maybe more people might show up.
Also someone who can write Japanese should go to Yahoo Japan and invite everone to come join our chat. Because they may like to talk with us but maybe they don't know how to join or are shy. Have you ever been to Yahoo Japan using the translated page? It's pretty funny.
I like having my own chats but you have to wait so long for anyone to show up.