While not always 100% accurate, retailer release lists often contain gems of information on game delays or unannounced releases. As the premiere videogame specialty retailer in the United States, keeping an eye on their release lists is at least worth the giggles.
Obtaining GameStop retail release lists doesn't require top-secret espionage tactics. As reserves are one of the companies key indicators of performance, employees are more than happy to waste reams of paper on providing customers with lists of upcoming releases.
Destructoid introducing their new monthly feature, "Sorted by Release," where they take a monthly look at any changes or oddities on GameStop's retail release list.