There are 10 new Trophies in this DLC.

Bronze

Lost Property    
No crimefighter should be without this    

Breaking and Entering    
Find a way into the secret base

Frequent Flyer    
Zip Kick 3 different thugs    

Battering Ram    
Shield Bash 5 different thugs    

Snap To It    
Snap Flash an unarmed thug, an armed thug, an environmental object and a Titan    

Bomb Squad    
Defuse all bombs in 3 minutes or less    

A Few New Tricks    
Use 5 different Quickfire gadgets in one fight as Robin in Harley Quinn's Revenge

Silver

How's It Hanging?    
Clean up the Dry Docks    

The Last Laugh    
The joke's on who?

Party's Over    
Destroy all Harley Balloons

http://www.ps3trophies.org/game/batman-arkham-city/trophies/