Lucky developers and Google I/O attendees who received an Android Wear watch and tried to use navigation commands must have noticed that this aspect of the experience wasn't working at all. Commands simply wouldn't carry through to the phone. This will all be fixed with the update to Google Maps version 8.1.1.
The update, which should be pushed to your device or coming shortly, squashes the regular bugs and adds support for Android Wear devices. The navigation and maps commands on the watches now carry through to the phone and are interpreted as expected. You can search for a location, start navigating, see directions, and exit when you're done, all from your wrist.
Now that the Android Wear SDK is out and the watches are available for pre-order, this is one of a deluge of app updates that we are bound to see in the next weeks and months - Google Keep and Google Play Services have already been updated. Exciting times!