TomTom is clearly the leading GPS device. Electronista is reporting a FCC filing revealing the TomTom DUO, a “handheld [that] would have support for a unique USB docking station in the style of a car stereo’s faceplate, allowing direct control of iPods.” The DUO will also offer Bluetooth and FM transmitter. The device is expected to be officially revealed at CeBIT expo in Germany next month.