Saw this from CES, looks like a winner. Available in March for under $1000, it includes navigation, DVD video playback, solid high-speed iPod integration, support for AAC, and numerous other features. Look for this one to get some serious penetration.
There is also a community for the AVIC line of receivers at AVIC411.COM.
UPDATE: Pioneer has the full details on the D3 posted online. Looks like iTunes AAC support is included now as well. I wonder if that includes Apple Lossless Codec support for playing ALC tunes from your iPod via the D3.