Android users now have the luxury of another free turn-by-turn option to choose from - Mappquest's free voice-guided nav app is now available in the Android Market. You can talk to it (search for destinations with voice); it can talk to you (it'll pipe up when you need to make a turn); and it has live traffic data refreshed every five minutes.
The app also uses the user-contributed OpenStreetMap dataset for offering solid (if potentially imperfect) international navigations, and future updates will likely bring the "My Places" personalisation feature over from the iPhone app. QR code below. [Search Engine Land]