I don't think it is necessary to request this one, for two reasons.
As mentioned before, it is doubtful that the technology is "there" yet.
Also, PD is already working with GPS related products and have been for a few years, now. What they are researching, though, is how to get real-world driving data into GT. They were actually working on the second-gen link to GT this year. I am pretty certain that if we can think of inputting tracks for GT from player-generated data, then they could, too. This idea has been around for a few years.
Ok, I just want to say a couple things about this. I think the reason that I'm so excited about this is that:
1. The technology IS there. Checkout:
http://www.strava.com2. The technology is ubiquitous. Every single human being over the age of 12 now owns a smart phone capable of recording the GPS data.
3. The technology is mature and proven. Over 10,000 cyclists use Strava regularly to record their rides and analyze the data.
4. It's somewhat easy to implement. All you need to do is define the data format and give the developer community an API to upload the data. There are hundreds of thousands of smart phone applications on the market, proving that developers will WRITE IT FOR YOU if you let them!!! I am personally volunteering to write the iPhone app for Kaz for free.
The points that have been raised are all valid, if the expectation is that the end result would be a close approximate to the real world. My only expectation is that the track would be the same distance, have a similar amount of elevation change and then be completely different than the real world otherwise. The technology doesn't need to be able to reproduce everything, just distance, elevation, changes in direction. And all of that is completely possible with today's technology using the common cell phone. Doing this would give the community a never ending supply of custom tracks and the game would literally never get boring. More than that, it would completely change the gaming industry by bringing the real world to gaming. It would change everything.
Just my humble opinion.