Here are the changes:
- Polygon creation now computes the convex hull. Vertices no longer need to be ordered.
- The convex hull code will merge vertices closer than dm_linearSlop. This may lead to failure on very small polygons.
- Added b2MotorJoint.
- Bug fixes.
svn checkout http://box2d.googlecode.com/svn/tags/v2.3.0
I plan to switch to this method for the next release of Box2D. Hopefully Google will make it easier to download a tagged version.