I really have no idea, what a "mining ship" could be.
With the addition of the drones and the added modules needed to launch and control them plus a refinery, I would expect a ship oriented to mining would have a higher number of smaller component slots.
Also, the announcement refers to mining being higher risk/reward so a mining ship would need to be able to defend itself.
So my guess is the Diamondback is a multi-role ship that's particularly suited to mining.