It appears that Here doesn't just reuse Google's traffic info (though it may be one of their inputs). If you aren't familiar with Here, they are Nokia's map/navigation arm that has spun off into their own company over the last few years, with a focus on embedded navigation. From their site:
HERE collects billions of GPS data points every day and leverages over 100 different incident sources to provide a robust foundation for our services. We use information collected from a variety of devices across the globe including smart phones, PNDs, sensors and connected cars. Our traffic experts also monitor incidents such as accidents and construction as they happen, 24 hours a day, 7 days a week.
They apply extensive knowledge and experience to decipher a range of sources including police radio messages, Twitter posts and traffic camera feeds.
Once collected, we process the data through our industry leading traffic engine - continuously updating our data every 60 seconds. By combining all our sources and expertly analysing the data in our incident management centre we regularly capture events that other services overlook.
