nice idea. but i wondering how many YAPC speakers are capable of moderate a panel like this?
but i would go for YAPC with or without it. ;-)
Good point. Maybe the conference organizers need to provide a designated facilitator. That person would probably be a volunteer, which means we'd probably need some sort of written guide for them. More things to document...
A similar sort of idea is used at the World Science Fiction convention (WorldCon) - an one hour round table limited to about 10 people get to talk with a SF personage. I got to spend an hour with Larry Niven and with Jim Gardner (not so famous, but he went to U of Waterloo and works for the same company as a friend of mine, so I have a connection with him), my wife had an hour with Harry Harrison.
Such an event is a mixture of gushing fan praise, with serious discussion (but that depends upon the particular individuals that sigh up). Panel discussions are also common at WorldCon, but those are open attendance sessions. (When you have a 4-day 20-track conference, you need a lot of different session to fill in the time slots.) The open attendance for these was critical. For one example among many I saw, during one panel discussion the talk went incidentally into rocket characteristics and an audience member who had been on the Saturn design team was able to comment authoritatively.