I've never had the money to collect comic books, so I learned about comic book characters from cartoons. I grew up favoring Marvel over DC. Marvel's characters lived in real-world cities, not Metropolis, Gotham City, Central City, or Coast City. Marvel's characters also seemed edgier, not all-encompassing like Superman, Batman, or Wonder Woman. Regular readers of this blog know I'm a Superman fan, but you can probably tell more about me knowing I'm a Daredevil fan.
My allegiance drifted toward DC with the premiere of Batman: The Animated Series. Its animation and acting were impossible to ignore, and subsequent projects have more or less maintained the standard while Marvel's cartoons lagged.
On the live-action movie front, I give the edge to Marvel since Iron Man, and with The Avengers: Earth's Mightiest Heroes on Disney XD, Marvel finally has a cartoon of comparable quality. Halfway through its first season, the show is telling classic stories of how the team formed, yet successfully giving them a contemporary spin—something Marvel comics do better than DC, in my opinion.
Though they are a team, the heroes still deal with issues unique to each of them. I don't get the sense of entering a vacuum from Avengers Mansion that I get from DC's Watchtower. Lastly, each episode ends hinting at a season-long arc, mimicking the feel of comics' "See you in 30" more effectively than the all two-parter first season of DC's Justice League.