Pioneer Woman writes "Microsoft announced plans to introduce a Web-based service for driving directions that incorporates complex software models to help users avoid traffic jams. The system is intended to reflect the complex traffic interactions that occur as traffic backs up on freeways and spills over onto city streets and will be freely available as part of the company's Live.com site for 72 cities in the US. Microsoft researchers designed algorithms that modeled traffic behavior by collecting trip data from Microsoft employees who volunteered to carry GPS units in their cars. In the end they were able to build a model for predicting traffic based on four years of data, effectively creating individual 'personalities' for over 800,000 road segments in the Seattle region. In all the system tracks about 60 million road segments in the US."