I have disagree profoundly with some of the work and beliefs of the colleagues you mentioned in your original post. I would love to discuss both the subtle and extreme points of disagreement with any of them in a public setting. The audience would certainly benefit from watching smart people discuss serious issues.
So, consider this a challenge to conference organizers. I would be delighted to share a stage with David or any of our other colleagues for a sustained substantive debate about the nature of learning, the role of technology or the future of learning. Just tell me when and where to show up!
I'm certainly in favor of poking holes in David's stream of convivial babble, but I have a crazy idea: couldn't we do this on blogs?
If you're going to consistently criticize a colleague/competitor in comments on their blog, you really ought to give them the same opportunity to come back at you on your blog, where you sincerely lay out your ideas (and no, The Pulse isn't enough). David has at least had the sand to do this, while folks like Gary and Alan November haven't, and, quite frankly, Gary and Alan have never given me the impression they understand the medium of blogging at all.