Ubisoft have announced, throught the official Playstation blog that a DLC pack called High Tides will see release on PS3 in January next year. The pack contains two new co-op levels - Jailbreak and Redemption - and is console exclusive to Playstation 3 (presumably they will arrive on PC, but no such information was released in the blog entry).
"High Tides will take place where the original six co-op chapters left off. These are the gang's final moments, and we're really challenging ourselves to go all-out. We've got new missions, tougher fights, bigger competitions, some great up-close time with your favorite characters, and explosive moments unlike anything you've seen before. Can you tell we're excited?"