Hi Jon Shipman,
Unfortunately it is not currently possible to style the dragging clue (the item being dragged). However, it sounds reasonable one to able to do so. This why we will add the following class to the clue for the Q3 release: rlbDraggingClue. Then you will be able to change the text in the item being dragged like this:
I hope that this helps. I've also updated your telerik points for the suggestion.
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