The auto-tracing of sprites is indeed a killer feature. Ray Wenderlich - Writer of awesome Cocos2d tutorials
If your favorite game engine is not yet available - no problem. The highly customizable output module of PhysicsEditor allows you to define your own data format.
It is even possible to add additional properties and features.
Automated Shape-Tracer is the feature that saves you tons of time when creating your collision shapes.
Simply press the MagicWand Button and PhysicsEditor uses the shape's transparency to create a perfect-fitting collision shape for you.
Adjust the accuracy of the trace to reduce the number of vertexes to make your game fast.
This example shows you how fast you can import and publish sprites using the Automated Shape-Tracer function.
The example is using Corona SDK, but will also work with any other framework.
You can download the complete source code from the tutorial.