A lot of the topics wouldn't require someone who is currently a 'core' developer. I think just about anyone who's written code for BeOS could teach (with a few weeks of preparation for themselves) a roomful of people how to write Replicants, implement effective Node Monitoring, utilize File-System Attributes, write a simple driver, port a few *nix apps, etc. It's not like this stuff is -difficult-. You just need to know what to do, and why you're doing it.If we can do a WalterCon @ BeGeistert in Europe then I'm sure that would be successful. I'm not sure whether there are enough core developers in the US to be able to deliver the "teaching" experience quite as successfully.
With that in mind, I'm certain we have enough devs in the US that could handle something like that, the problem is that over the last three years WC hasn't proven to be beneficial for those individuals, and now they're not attending. To get them involved again, you'll need to convince them that WC07 will be worth their time.
Even if we only had two or three people that could teach, they could each cover multiple topics in different sessions that run fairly long. Longer sessions would probably encourage more in-depth practical application of the topic. This is not a bad thing. If there were only four or five sessions over the course of two days, taught by two or three people, then I think WC07 would have some -serious- value for developers that want to -learn-. I'd pay money to attend, and I'd offer to teach something if I could make it.