Most of the major aftermarket car audio manufacturers had booths at the Tokyo Motor Show, and they all showed off high-end head units that combine music and video playback with navigation. The units in general use a double-DIN form factor with a 7-inch LCD-motorized touch screen. Slots accept DVDs and CDs, and the units display ID3-tagging information from MP3s. I also saw many with iPod integration that goes a step further than any current auto manufacturer-installed integration. Song information is displayed on the head unit's LCD, and full navigation of the iPod is available. The only element I haven't seen in a head unit is Bluetooth cell phone integration, but I can't imagine that's far behind.
These units have two major drawbacks: one, they lack space for controls, and two, the LCD takes up too much stowed space, forcing the double-DIN form. Although the touch screen is a flexible control space, it's nothing like having integrated steering wheel buttons and a center-mounted joystick or knob. Also, double-DIN slots that can visually and practically integrate an aftermarket stereo are rare. Some companies are releasing organic LED displays, which promise to be much more compact. I'll be reporting more on these from SEMA, the big aftermarket show, in November.