When I check the page of Yoyogi YH it's apparent that they got no rooms left, at all, for 27th Dec 2006 and onward, it's in the midst of the holiday season and I belive a lot of people is going there around that time. I'm planning to go there for CDL 06-07, I might have a place to stay for free, but if not I was planning to stay at the YH.
It also seems like you can't book rooms for the coming year yet, by some reason. I'm going to contact them as soon as I get back home (later this evening) and I'll post information here as soon as I get a reply.
Glad that my efforts could be of help, and it's quite possiblee that we'll see you around in Tokyo 2007
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