Emergence for Sat Navs & avoiding traffic

I have been thinking if there is any way that we could make sat navs more intelligent and get them to provide usefull data for other vehicles to use. Now that you can combine your mobile phone & sat nav into one device it is very easy for the sat nav to send info back to a central server that anyone can access. What would be the point? Well, the sat nav will know what road you are on and what the average speed should be on that road. If your speed then drops to say 1/3 of what it should be, the sat nav could send this info to a central server. If quite a few sat navs were doing this you have immediately got an up to date traffic service (including for all the alternative routes as well). Your clever little sat nav could then retrieve this data and plan you an alternative route (and maybe even tell the central server what that is). With a few clever algorithms to server could keep track of which alternative routes people are taking and make sure that everyone is not redirected the same way. Could this be the future for Sat Navs & traffic...maybe