I might be missing the point here but what's to stop developers from building a Windows Phone application that utilizes the tile sources from google maps which

I might be missing the point here but what's to stop developers from building a Windows Phone application that utilizes the tile sources from google maps which uses the Google Directions API for routing purposes? See: http://dotnetbyexample.blogspot.co.uk/2010/10/google-maps-for-windows-phone-7.html http://dotnetbyexample.blogspot.co.uk/2010/10/google-maps-fo... I did a similar project a couple months back on the WP7 platform and ended up using OSM + ORSM instead.