NAVIGON dropped us a note to say that, as promised, their latest update to MobileNavigator [$89.99 for North America - iTunes link] for iPhone is now available via the iTunes App Store, and it includes Traffic Live as an in-app purchase (currently on sale at an introductory $19.99, $24.99 thereafter). Here's how it works:

Traffic Live utilizes crowdsourced real-time speed data from over 1.3 million drivers including other NAVIGON app users (who opt. in to participate), commercial fleets such as trucks and taxis, as well as regular drivers with a GPS system. So if for example several vehicles on a road report slow speed, the system recognizes congestion and provides an alternate and faster route.

If you add the Traffic Live service, let us know how it works for you.