Comics now have more options than every before to add to a game.
Berserk, the manga, volume one is finally out. Great stuff for a grim world with supernatural horror.
The Cursed Sword has some pretty interesting elements.
Of course traditional super hero comics have their place. I agree that NPC use and situations are all good and useful but I've had problems with introducing long term villains that continue to scale in power. Unlike the comics, most characters are on a continual increase in terms of their power level and if the villains do not scale, will quickly become outclassed.
Of course this doesn't matter for those NPC's who aren't combat oriented. After all, how often did J.J. Jameson actuall physically go after Spider Man outside of a few stupid robot tricks? No, these NPCs will heavily rely on the law, their own financies, their own allies, friends, and if necessary, other things like cursed items, untrustworthy servants and even perhaps, changing their humanity in for power via template acquisition.
Long live the comic!