i've been experimenting with
this app for a while. It does bring some of the basic traffic real-time/predictive information, but mostly limited on freeways. It appears to a prototype of next generation traffic data provider/collector -- yes, it could use the information your cell phone provides. Here is what its website claims:
"Every driver in the network anonymously and automatically sends their
speed, position and heading to INRIX Smart Driver Network servers.
INRIX intelligently combines your information with real-time data from
other drivers and traditional road sensors and then instantaneously
updates the traffic maps on INRIX TRAFFIC! Everyone in the network benefits from up-to-the-minute, accurate traffic information with superior road coverage.
"
To really make this work, there are still a lot to do. One needs large sample sizes to ensure the quality is reliable, and some sort of smart algorithms to make the best out of the data. In addition, it could be more useful to users if it can be combined with a navigation system, or at least has some sort of voice guidance on potential congestion based on our current location/speed. And last but not the least, the battery life of the phone could kill this sort of app -- not sure about others, but i'm quite concern about how fast the battery drains when location service is left on...