Just to throw my two cents in as an '07 panelist:
There almost needs to be a Panelist/Exhibitor reg form to go along with the Panel/Exhibitor table reg form. It wasn't an issue this year for me because I registered when the pre-reg price and the Panelist's listed discount were the same, but it would still be nice. It would also be a benefit to mail out Panelist/Exhibitor badges if such a form was created.