I've used all three and have tended to favor white boards, usually with everyone present spending a few minutes at the end trying to copy on their notepad what they need.
I'd be interested to see how a tablet PC goes over (HP feel free to send me one) since we have overhead projectors in all conference rooms.
I hadn't considered flip charts, but the few times I've used them, they've worked well. All in all, having something everyone can see is the best solution for group discussions.
Steve Jones
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