Google Maps have added a traffic predictor to Google Maps. Now when you press the 'traffic' button (which only appears in the areas that Google provides traffic data) a new traffic control will appear on the map. You can view the live conditions, or click "change" and it will let you see average traffic patterns in the area at any hour on any day of the week. The predicted traffic is based on past conditions on the selected roads.
Google Maps is also now displaying accidents, construction, and road closures with small icons on the map. Clicking on the icon will give you details of the hold up, including an estimate of when the problem is going to go away.
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