WCE traded picks 12 and 28 to Adelaide with an agreement that they would upgrade pick 28 if they received anything else (stuffed if I know why, that is plenty for him already). So Adelaide is waiting to see if WCE can get anything else before signing off on that deal.
That deal holds up the Thompson to Adelaide deal
Which holds up the pick 12 to Geelong for Moloney deal
Which holds up the Ottens to Geelong for pick 12, 16 deal
Which holds up the possible Zantuck and 12 to Carlton for picks 9 and 41 to Richmond