I continue to be amazed. check this new service out. granted there aren’t too many cities yet and only a few cab companies but still another interesting progression of ideas. google has such a broad palette to work with. I sure various other local organizations may have had the ability to put together something like this on a local basis (King County Metro system has something similar called tracker but only with the buses and not nearly as smooth) but google will have the resources to implement this on the larger scale. i wouldn’t imagine this was that difficult to put together. the gps already exists in the cab companies in large cities through a better portion of the us. collect all the information and present in a nice little package that everyone will know about.