The right place would be to email the contact email on http://www.dreambuildplay.com/
I seem to remember somebody asking for this lat year though and I don't believe anything happened. I would postulate that this is for 2 reasons:
1. Just too many entries to reply to - it takes a lot more time to review if people have to make more extensive notes.
2. Any response that comes from Microsoft would need to get some kind of legal review for consistency and objectivity otherwise one or 2 people would immediatly blog the feedback ripping Microsoft for choosing others over their game in a huge display of sour grapes... there was actually some of this in the fourms last time too.
Why not put the ccgame on your website on on community games - you KNOW most people in this forum love to give constructive criticism.
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