Tripwire Interactive just announced that they will now be self-publishing, starting with the retail version of our own Steam hit zombie co-op shooter – Killing Floor. Tripwire will be the publisher for Killing Floor in North American stores, with the boxes due for shipping to retail outlets in USA and Canada shortly. As always with Tripwire titles, the retail version will be fully supported going forward with additional free updates for the game. MSRP will be $19.99 in the USA.