One of the most important changes for new GD Custom Posts and Taxonomies Tools Pro 3.0 plugin is updated and improved interface. Work on that has already started, and you can see here an example of the editor for a post type. Taxonomies will use similar editor layout.
With more and more options added for post types and taxonomies registration, current editor is not very user friendly, with tons of settings put together. New interface splits settings into tabs and adds tooltip information about options. Also, it will use AJAX to save settings with improved validator.
Styling and layout is similar to one that will be added to GD Star Rating 2.0, and is evolution of interface used in xScape Theme Framework.