The people at PS3Trophies have spotted some new trophies for an yet unannounced
Dishonored DLC named
The Other Side of the Coin. The 10 trophies are at the
bottom of this list.
Based on available information the second and third DLC for Dishonored are supposed to be story based, which would be applicable to this DLC, but as this list is the only information available we'll have to wait and see.
More information.