Moderators are a key part, definitely. The really important thing is to ask the tough questions. The worst panels are just love-ins, whereas - especially on more business rather than tech-focused panels - the good ones are where tough questions are asked and product pitches are kept to a minimum.
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The moderator definitely plays a big part in how well the panel goes. I've been to some pretty bad panels, but I really liked the AJAX panel.
Moderators are a key part, definitely. The really important thing is to ask the tough questions. The worst panels are just love-ins, whereas - especially on more business rather than tech-focused panels - the good ones are where tough questions are asked and product pitches are kept to a minimum.