With news of NFS: Rivals being added to EA Access, it was noted that 245k hours of Madden was played, and Joystiq's napkin math puts the subscribers at just south of 41k.
I didn't play my 6 hours, wouldn't be surprised if the subscriber count was significantly higher since Madden isn't the only reason to get the service.
http://www.joystiq.com/2014/09/03/ne...a-access-soon/