Gumdrop Cases has unveiled its new Moto Rubber and Skater Nation Plastic cases for the fourth-generation iPod touch. The Moto Rubber is a form-fitting TPU case featuring a motocross tread design and open access to all ports, controls, and cameras. It is available for pre-order in three colors and sells for $25; for more information, see our First Look article. The Skater Nation Plastic is a lightweight polycarbonate case featuring a snap-on design, a soft-touch exterior finish, and open access to all ports and controls. Like the Moto Rubber, it is available for pre-order in three colors and sells for $30; the Moto Rubber is expected to ship on September 15, while the Skater Nation Plastic should ship on September 30.