Warren Ellis's run on Storm Watch for one. Anything by him really. The fact that every other random word isn't bolded and the dialogue actually feels natural instead of being melodramatic.
Fight smart, not fair.Joss Whedon's Astonishing X-Men
Most of Ultimate Spiderman.
Planet Hulk, World War Hulk, Incredible Hercules, and most other stories written by Greg Pak.
My favourite comic book writer as far a dialogue is concerned is Peter David. Sharp, witty and packed with pop culture references. His two runs on X-Factor stand out in paticular. I'm also fond of J M De Matteis work on Justice League International. I've also recently rediscovered just how good Alan Moore is at dialouge, my attention having being focused on all the other aspects of writing he's brilliant at.
Alternatively you could explore some of the more unique comic book dialogue out there. Stan Lee's is incredibly corny, but I find it captivating in it's own way. Kirby's dialogue in The Fourth World comics is very strange indeed. Bendis has already been mentioned, there are people who love it and people who hate it. And Chris Claremont examplifies the kind of overwrought style that is present in so many comics.
Am I a good man or a bad man?I loved Claremont's ability to develop characters, and a lot of his dialogue could be very strong, but I'd occasionally get the impression that he didn't completely trust his artists to get ideas across visually. He'd often disrupt his pacing by having characters go into lengthy internal monologues in the middle of fight scenes. His attempts at humor often fell kinda flat, too.
I'm going to second Peter David. I'll also say Christos Gage, who started off as a screenwriter.
X-Men X-Pert, my blog where I talk about X-Men comics.I second Warren Ellis. That man writes damned good dialogue.
Eh... I disagree that that makes for good dialogue. If anything it leads to stuff ending up as appearing dated - vague allusions are fine but overall I think references should be at a minimum.
But I agree that wittiness is desired.
Come to think of it, don't think I've read any Peter David. Gimme yer lunch money, dweeb.
Never read Peter David? Probably because you suck.
Incredible Hulk, X-Factor, Star Trek: The Next Generation novels. He wrote the Death of Jean De Wolff for Spider-Man, and he wrote Spider-Man 2099. He also had notable runs on Aquaman, Supergirl, and Young Justice.
Not everything he's done has been great. But most of it has. Clever, witty, dramatic, character-focused, he's just an awesome writer.
X-Men X-Pert, my blog where I talk about X-Men comics.

Hi, comic board! I'm a lurker-turned-poster here and wanted to know what some of your all-time favorite comics/graphic novels are for dialogue. I'm looking for things that can be acted out in readers' theater. Any suggestions? I've heard Neil Gaiman would be a good place to start. Please give some background to your picks, i.e. WHY you think it's good and would work. If I get good suggestions and the readers' theater experiment goes well, I'll see about posting some of the readings on You Tube.