[quote name='CloseConfine']wats EDGE?[/quote]
It's the GS discount card. It entitles you to 10% off used games and accessories, as well as an extra 10% credit when you trade in games and accessories. It costs $15 for a year, and you also get a year's subscription to Game Informer, which is distributed by GameStop. I have heard, though, that GS was toying with a $20 price point.
Though the 10% doesn't seem like it much, it quickly adds up, if you like to take advantage of their deals on used games. For instance, if you were to use their latest coupon, 25% off used Sony console games, and you got three pretty new PS3 games that they usually sell for $55, you would be getting $5.50 off each game, already paying off the cost of subscribing.