I see that the new unit is about to be realesed, Anyone have any info on it?

 

prolly just updated maps, and slight graphics refreshment. If you have a d3 it wont be worth you upgrading.
The Z3 is supposed to get a huge upgrade in the voice control dept. the new system is supposed to be designed by microsoft.

 

There is so such thing as the D4. Pioneer's new navigation is the F series and it should be out in June of 08.