The multiplayer Factions mode has recieved new add-ons including new weapons, clothing, and gestures.
All the DLC items can either be bought bundled together in various packs, or bought individually for a reduced price. Check out Naughty Dog's update to find out more.
The new DLC adds new takedown animations ($0.99 each, and some aren't available on PS3 due to hardware limitations) across nine different weapon categories, along with four new weapons ($0.99 each or $2.99 bundled) including a crossbow. There are new survival skills (£0.99 each or $3.99 bundled), head clothing items ($6.99 bundled or 'various prices' on their own), and gestures ($0.99 each or the bundles are $2.49 each).
Here's the trailer for the new DLC below.