There are two key differences...studio independence, and Kevin Feige.
DC are at the mercy of Warner Bros. The reason marvel are able to successfully transition characters like Guardians of the Galaxy from the pages where only the hardcore know them, to the screen where they are embraced by the masses is due to the fact the studio is run by comic book fans, which allows them to take greater liberties with unusual characters and situations. DC still have to answer to a bunch of suits who, due to being unfamiliar with the source material, may not allow as great liberties to be taken, instead going for the safer route.
Then there's Feige, who is the main man behind the marvel cinematic universe, and the reason it has successfully intertwined characters and story lines the way it has. Feige is the man with the plan, and in his mind will know exactly how every movie relates to one another. To my knowledge DC don't have a puppet master in the mould of Feige