Sure, there are billboards hawking everything from mattresses to legal services along most populated routes in many countries. But we've grown accustomed to them, and at the very least they don't invade our personal space. The in-car ads, on the other hand, are expected to function much like ads on the internet or on ad-supported software.
Worse - or better, depending on your point of view - the system could feature targeted ads, meaning you'll get ads for places on your current route, or free MP3s could be downloaded to your Sync-equipped car while you wait in line at a Starbucks drive through, reports CNet. How long until the first Microsoft car-virus gets spread this way?
The proposal is a practical one, however. Supplying such detailed and time-sensitive information as traffic and weather to local customers is expensive. Absent some sort of subscription service, the only alternative - and the only one likely to gain mass appeal - is the ad-supported model. And there's something to be said for on-demand traffic, weather and route information. The question is whether it's worth your peace and quiet.
Whatever your stance on the subject, we'll have several years to prepare - this is a longer-term goal. It's not expected to reach any sort of tangible reality until at least 2012 or 2013.