If you're considering purchasing Madden 13 when it is released on August 28th, you should also think about preordering through Walmart. In fact, if you're a Broncos fan who plays madden and DON'T purchase through Walmart, you're going to be angry that you didn't.
The new version of Madden allows players to assume the persona of various legendary players as they go from rookie to Hall of Famer in a game mode called "Connected Careers". It's similar to previous versions of Madden's Superstar mode. However, featured in this game are Denver Broncos Hall of Fame tandem of Shannon Sharpe and John Elway.
Unfortunately, John Elway is only available for those who preorder their copy of Madden through Walmart. So, if you want to replicate Elway's career with your own virtual football skills, you must purchase your copy through Walmart. The link to Walmart's preorder page is found here.
Enjoy the new Madden... if you're into that sort of thing.