I may not personally follow the sports gaming scene, but I can appreciate what EA has done here. Releasing July 27th Madden's demo will feature the New York Jets vs the Indianapolis Colts, and will apparently be very detailed. Players will more or less be able to get a full game's experience, with exception to being able to select only one of two teams.
The demo will also feature a lot of other neat bonuses, such as being able to preemptively unlock achievements, test some of the new (and updated) game modes, and get a unique Ultimate Team Card which will be usable in the full retail version of the game. The entire demo reeks of fan service, which is fantastic because that's what gamers love the most.
The the Jets vs Colts matchup was also determined by the fans, so really there's not a lot to complain about here. At least if you enjoy football.