Hi Mike,
As I recall, during the SDK Beta Program we were advised against trying to manually load a newer version of D3 via the include tag in the contribution.xml file to avoid causing conflicts with the standard D3 library included in DS. Technically, I suppose you could load your own version of D3 if you could guarantee that no other components based on the DS standard D3 version were going to be used in the application.
Perhaps the DS Team can confirm if the above position still applies.
Mustafa.