Last night we happened to catch a cab outfitted with the new seat-back TV screens. The right side runs video ads for Broadway shows and other touristy destinations, while the left side contains a GPS map showing the cab’s location. You can also scroll the NYC Zagat guide. I suppose the location marker could be handy, except that our map showed us moving briskly down the Garden State Parkway outside of Secaucus, New Jersey. However, the “off” button worked nicely.