As much as you'll find a lot of Superman talk around The Signal Watch, I'm also a fan of The Dark Knight Detective.
Batman has been around almost as long as Superman, and its likely there's as much or more in the way of Batman in print out there as The Man of Steel. Reader Mike F. pinged me on Twitter. He's been reading the superlative "Batman: Year One" by Frank Miller and David Mazzuccelli. Which, if you like Batman but don't read comics, you owe it to yourself to read this comic.
There are a few ways to answer the question of "what do I read next?" Do you read more Frank Miller? More David Mazzuccelli? Or more Batman?
Well, I'm generally always going to recommend reading more Frank Miller and David Mazzuccelli. So let's talk Batman.
The biggest problem with jumping into Batman comics at the current date is that the monthly Batman comics are knee-deep in an ongoing, multi-year storyline (in which Bruce Wayne is not currently Batman, btw). So I don't recommend heading down to your local comic shop at the moment unless you're interested in picking up either "Superman/ Batman", "Batman: Confidential" or "Batman: The Brave and the Bold", all of which are intended for various audiences, but all intended so that a reader can pick up Batman comics any time without feeling like they just walked into the third act of a movie.
I've tried to put these comics down in the order in which I think they should be read. I've also provided a "Required Read Level" or "Req Level", to help you judge how necessary this story might be to understanding subsequent comics. And, of course, this is my opinion and my opinion only. Counter arguments, suggestions, etc... are all welcome in the comments.
I should also note: There's a period in the mid-90's when I simply wasn't reading Batman. I abandoned Batman just prior to "Broken Bat" and didn't return to read "Contagion" or any of the earthquake/ "No Man's Land" stuff. I sort of regret not reading more of the "No Man's Land" stuff, but there you have it. I came back around 1998, and have been reading fairly steadily since. I invite other Bat-fans to join in with their take on what I might have missed, or to argue some of these "Required Reading Levels".
Batman: Year Two (Req Level: High) This comic isn't bad, but reading it reinforces the notion of what a feat Miller and Mazzuccelli pulled off with Year One to lift Batman out of the standard tropes of superhero comics. Mostly, Year Two serves an important function from a chronological standpoint and to answer some of the questions you might have about decisions a young Bruce Wayne would have had to answer early on in his career. The series is occasionally referenced in other media and the Batman comics.
Batman: The Long Halloween (Req Level: High) Jeph Loeb tells a great story, adding on to Batman's early career, following a pre-Robin Batman as he passes through a year of dealing with his rogues gallery, Gotham mobsters and a mysterious set of murders.
Batman: The Mad Monk and Batman and the Monster Men (Req Level: Low) Not a necessary read, but a darn good one. 80's comic legend Matt Wagner came roaring back with retellings of some of Batman's earliest and greatest stories from the 40's, integrating them into continuity. It definitely leans more toward superhero-ism than just detective work and the gritty feel of Year One, but its great to see DC making an effort to keep some of these original tales alive and updated.
Robin: Year One (Req Level: Medium) I was pleasantly surprised how much I liked this particular comic. Retells the origin of Batman's sidekick from some of Batman's better writers.
Batman: Dark Victory (Req Level: Medium) The follow up to Batman: The Long Halloween.
Batgirl: Year One (Req Level: Low) A fun read. The origin of DC's Batgirl.
Batman: Son of the Demon (Req Level: Medium) A favorite 80's-era tale of Batman versus Ra's Al Ghul, one of the most interesting of Batman's Rogues Gallery.
Greatest Batman Stories Ever Told (Req Level: Low) Not really necessary reading, and the copy I have was originally timed for release with the Tim Burton-directed Batman film, so you can guess when they quit adding stories to the volume. But its a nice slice of Bat-history in one, very readable volume.
Greatest Joker Stories Ever Told (Req Level: Low) A very similar read to the Batman volume, but featuring tales starring the Clown Prince of Crime.
Batman: A Death in the Family (Req Level: High) One of the most important Batman stories, this four-issue series would be one of a few comics to dictate the direction of the Batbooks for 20 years.
Batman: A Lonely Place of Dying (Req Level: Medium) This series followed not too long upon A Death in the Family, and pulls double duty as Year Three and introducing the third Robin, Tim Drake.
Batman: The Killing Joke (Req Level: Highest) Perhaps the most iconic of all Batman/ Joker stories, The Killing Joke defined how a generation would interpret The Joker, and his relationship to Batman, ultimately spilling out into the movie The Dark Knight. As a kid, this comic melted my brain.
Arkham Asylum - A Serious House on Serious Earth (Req Level: High) A personal favorite. This comic would establish Arkham as far, far more than just a jail for Batman's villains. Today's readers will know the series mostly due to the influence its had on the current Batman titles and the game it helped spawn that sold millions of copies and is due for a sequel. Morrison's writing and McKean's surrealist imagery form an hallucinatory exploration of the archetypes of evil Arkham is damned to contain and create. Its also one of those comics where writing and art gel to create a work that seems to stand outside the genre and form. Unfortunately, its also led to a lot of half-baked attempts to milk the initial concept.
Batman: Hush (Req Level: Low) While I enjoyed Hush, and it was certainly a highlight of the post 2000-era Batman, this story seemed to generate more trouble than it was worth. However, it does contain key plot points and introduces the villain, Hush.
Batman and Son (Req Level: Medium) The first chapter in the current storyline for Batman comics. Spins directly out of the 1980's Son of the Demon comic. The beginning of an epic, multi-year arc.
Batman: Whatever Happened to the Caped Crusader? (Req Level: Low) While not required reading and hardly in continuity or canon, this story is an odd farewell to multiple visions of Batman as seen over the years.
A Special Mention:
Batman: The Dark Knight Returns (Req Level: incalculable) Probably the most important comic post 1945, The Dark Knight Returns isn't even in continuity, but Frank Miller reset how three generations would think about Batman, superheroes, and the content of superhero comics. It would also, artistically , change the form of the superhero comic forever. Rife with political satire, unpleasant truths about our caped heroes, and perhaps the first real look at how superheroes might play out given time... It also set up generations of people to think Superman was kind of dumb (which was always kind of missing the point).
Some Additional Batman Reading:
Batman: War on Crime A standalone, painted Batman oversized comic. Beautifully told and rendered, and cutting to the core of what makes Batman work as a character.
Gotham Central A series about the police force operating in Gotham City. The series was never properly appreciated in its time.
JLA: New World Order Grant Morrison reminded us why Batman is so crucial to the JLA in a few short issues. Would establish Batman's presence within the DCU for the next 10 years.
Nightwing: Year One
DC Comics Classics Library: Batman, The Annuals Batman used to be really goofy. I don't know what else to say about it.