On the heels of yesterday's post about voice-guided, subscription based turn by turn navigation apps on the iPhone (and the impending death of the PND market) comes AT&T's entry with AT&T Navigator. It's feature rich (though I haven't used it) and costs $9.99 per month. The wrinkle here is that you're not billed through iTunes, but directly through your AT&T bill (no 30% tariff for AT&T).

Here are the features verbatim from the release: 

• Automatic Content Updates: No manual updates required. The latest map and navigating details are automatically available to subscribers at no extra cost.
• Voice and On-Screen Turn-By-Turn Directions: Real-time voice and visual guidance, including street names, automatic re-routes, ETA and total mileage updates. Drivers can also choose among multiple route options, including 'traffic optimized'; 'fastest'; 'prefer streets'; 'prefer highways' and 'pedestrian mode' to ensure the most customized navigation experience.
• Speech Recognition: Touch and talk capability for instant turn-by-turn directions to destination.
• Traffic Alerts: Real-time route monitoring and proactive searches every five minutes for traffic congestion or incident. Voice and on-screen alerts, plus faster route options provided.
• 3D Maps: Full-color 3D moving map brings navigation to life. Maps provide details on current location, plus streets and interstates within driving distance.
• Business Listings: One-touch access to more than 10 million business listings from YELLOWPAGES.COM. Plus, access to business ratings, phone numbers and one-touch dialing.
• In-Route Customization: Users have the advantage of finding convenient rest stops for gas, food and other needs along their current route - saving both time and mileage.
• Online Trip Planning: Preplan trips, save addresses and manage travel accounts online at www.navpreplan.com. Save locations and send directions straight to iPhone.

It also provides business listings from AT&T's Yellowpages.com subsidiary. This is now the second, voice-guided GPS directions app for the US and the fourth to hit the market (not counting TomTom) since the 3.0 software update and iPhone 3GS launch.