I think Eduard brings up a good point about discussions as discussions. Training can be rather focused, targeted, and narrow, and sometimes this is appropriate to meet necessary constraints. But discussion can expand training into something else--creating knowledge and collaborating toward unique solutions. With discussions, an instructor or trainer gives up a little control, but what is gained is opportunity to go places unplanned.
I am intrigued by Eduard's suggestion about Google Wave. I hope we can collaborate with this tool in the future. Maybe a "course" that is not a course, but a collaboration toward a general goal. I have hoped this session could be a little like that.