http://www.soccerbythenumbers.com/2011/05/how-much-football-is-there-in-match.html is titled "How Much Football Is There In A Match?"
That site said the ball was in play for 62.39 minutes per game in the 2010-2011 EPL. http://www.soccermetrics.net/team-performance/effective-time-in-football disagrees and says 55.1 minutes.
In today's AS Roma-Genoa game, at halftime BeIN Sports gave "ball possession time" for each club that adds up to 22:44, which is 50.5 percent of 45 minutes. 22:44 is a pace for 45:28 (45.47 minutes) for a game, which is significantly fewer than the 62.39 minutes in my previous post.