I'm new here, so hi everyone!
The documentation states about WorldAnchor: "WorldAnchor1 – Get the world anchor for Body1. Useful for drawing the joint."
But from my experimentations, WorldAnchor indicates where the world anchor position was the previous timestep - at least for the PinJoint. Using the following code; "PinJoint.Body1.GetWorldPosition(PinJoint.Anchor1)" returns the correct position.
this becomes very visible when rendering a joint for a fast moving body.