In the latest version of the API, we're introducing utility functions to give you more information about your lines and shapes: GPolyline.getLength, GPolyline.getBounds, GPolygon.getArea, and GPolygon.getBounds. Below, I've modified the code from the E-Z Digitizer tutorial to show you the length or area of the drawn poly, and let you zoom to the bounds of the drawn poly.
Check out the documentation for more information, and post in the forum if you have any questions.
