Ah, too bad! I'm just about to move out of Tokyo. I would have loved to participate in a LW gathering here otherwise.
There's a ~20% chance that I will be back in Tokyo next year, for a period of a few years. So you can count me as 1/5th of an 'interested' response
I'd like to gauge interest in an (english-language) Tokyo area meetup - given Tokyo's size, if a couple people are interested, it would be good to pick a location/day that's convenient for everybody. Otherwise I will announce a date and time and wait in a cafe with a book hoping that somebody will turn up.
I have been to several LW gatherings and have met consistently awesome and nice people, so if any Tokyo lurkers are reading this, I can assure you it's totally worth it to come! Please make yourself heard in the comments if you are interested.