One pattern I've noticed is that, in recent years, DC's comics seem to be more traditional superhero fare (Blackest Night, Throne of Atlantis), while Marvel tries to be more grounded and present real-world allegories (e.g. Civil War, Fear Itself).
But funnily enough, their adaptations in other media are the complete opposite. DC's adaptations seem to be more serious (BTAS, Young Justice, The Dark Knight Trilogy, Man of Steel), while Marvel's adaptations embrace the fun part of superheroes (Avengers Earth's Mightiest Heroes, Ultimate Spider-Man, the Marvel Cinematic Universe).
Of course, there are exceptions on both sides, but I'd like to hear what you guys think about this. Has anyone ever noticed this before?