Well, they may not be "real" PKs but they sure act like them!
The wilderness is a little more dangerous with the arrival of various murderous reds seen in remote areas. They have also made Buc's Den their main base, once again living up to the town's lawless reputation.
You'll recognize them by their guild tags and red names. If you manage to take one down you will collect the insurance value of their gear, paid directly into your bank box. They just might have more useful items too. Just like "real" PvP, you never know what may be in their pack. They use bandages and potions to stay alive and they are well-versed in their weapon's special moves.