The difficulty for Google is to keep up with all of the transit options, especially when it comes to live information. Today, it announced updates for NYC, D.C. and Salt Lake City, which will show you live departure times for seven lines on the NYC Subway system (MTA) and buses, subway in D.C. (Metrorail) and trams in Salt Lake City (UTA). There are more than 800 cities with transit information available in Google Maps, but these three cities are getting more attention, since they have the most riders.

Google Maps has been a massive success since launching on iOS last December, and transit information is a huge advantage.

Photo Credit: Google shows off live transit updates in Brooklyn, New York. Google BlogG