I read Guy Kawasaki's rules (via my pal Don) for panel moderators and he missed a whole lot of things. First, go read it:
Bona tempora volvantur--by Guy Kawasaki: How To Be a Great Moderator
Now, here's the things he didn't say:
1) Panels are an audience rip off. They distill any valuable information out of the system. Very few panels are worth attending. No one on a panel does any real work leading up to it because anyone with any experience talking can bs through 10 minutes and questions from an audience or moderator with no preperation.
2) Panels are a sponsor perk. Conferences, to give their sponsors promised slots, will fill panels.
3) Any show that has more than 1 panel per ten conference sessions that is -not- a science fiction convention or similar hobby oriented thing, isn't worth going to. Period. And at most it isn't worth paying for. Okay, unless you are the one selling stuff. But even then.
4) Any panel with more then 4 panelists is worthless. Too many people to present anything cogently.
5) Any panel with more than 3 panelists is likely worthless.
6) Panels are a great opportunity to check email, if the conference has wireless.
That is all. I was in a panel recently, run by Apache's Susie Wu that didn't suck, and there was a minimum of laptops open (surfers) and such, so yay us.