Washington - Oct 25, 2006 - Arbitron has revised its Portable People Meter (PPM) roll-out timetable in an effort to deploy the service quicker to the Top 50 markets. Philadelphia will begin using the PPM service starting in January 2007 and New York will begin using it as of July 2007. Los Angeles is schedule for the PPM service in October 2007. For more information about the Top 50 market PPM deployment, visit www.arbitron.com/portable_people_meters/home.htm.