I share your same feelings.. I wish I had the opportunity to share my ideas and thoughts with the others.
I liked the moderator idea as well, but I wish there was a "whole room" brainstorming as well.
There was a time when this happened (kind of) when we were making up new metaphors for MaStory.
It was funnier to share your thoughts with everyone else.

In general though, I really liked it.

We developers needed to be taught those general concepts regarding concepting, usability and graphics of a UI and this was, I think, a good way to do it.

Aniello