Having recently switched from iPhone to Nexus One, I have been really impressed by the functionality and ease of use. On a recent trip to Victoria, I decided to test out the new Navigation features of the Nexus One using the Car Dock. The Car Dock is available from Google or a number of other resellers. It keeps your device constantly charging and also turns the Nexus One into a speaker phone (legal in most states, provinces).
Here is the video of the recent test. There are also a few drawbacks. One wish is that the Bluetooth stayed connected while in the Car Dock. For some reason, as soon as the Car Dock mode is engaged, Bluetooth headsets no longer work. This can be annoying if you want to make a private call with other passengers in the car. Other than this minor nit, I give it a solid 10/10.