I will count down, in order to create an air of excitement.
(Notable exclusions include: The Authority, which I loved in its early days but have found progressively more irritating as years have gone by and, I believe, they're now folding it in to the main DC Universe anyway; Welcome to Tranquility is generally well-written and endearing, but has never quite grabbed me enough to keep me hooked, but I do admire Gail Simone; finally, there's The Intimates, which was just got a bit too trippy by the end. All worth a read though!
So... now to the Top 5!)
Invincible is the ongoing story of a teenager who finds out that his dad is the world's premier superhero (basically a Superman equivalent), but then discovers that said dad is actually an evil alien, infiltrating humanity in order to prepare for a full-on invasion for his people. So it's basically all about the lead character (Invincible), coming to terms with that, and becoming a hero in his own right.
It's very traditional in its storytelling, and art style, but quite current in voice, and has some interestign things to say. I slightly dropped off from reading it recently, and am a few trades behind, but I always enjoy it when I do eventually get round to reading it.
Recommended for: anyone who's got an interest in superheroes but is intimidated by Marvel and DC continuity. Also, teenagers.
4. The Boys
The Boys is just bad-ass. It's by Garth Ennis who brought us Preacher, The Magnificent Kev, and some classic issues of the Punisher. Its audience is its title, but all the ridiculous violence and knob-jokes aside, it can be a pretty intelligent read, and is almost always engaging. The main characters, even the everyman Wee Hughie (whose look is based on Simon Pegg), can be unlikeable bastards, and some awful things do happen in it but... it's just so entertaining, and carried off with such confidence, that it's hard not to find the book charming anyway.
Recommended for: Blokes, largely, but ones with brains. Men who read Viz or FHM would probably love this.
3. Astro City
I once went for dinner with Kurt Busiek, don't you know. I didn't tell him how much I loved Astro City, but I wish I had.
These books are set in a city full of superheroes, and are largely told by normal people living there who witness these gods among men. It's largely an examination into how the existence of superheroes would actually affect the world around it, and it runs the gamut from wide-eyed wonder to the huge insiginificance one would feel being surrounded by these gods.
It's all told in a very personal way, in a very Busiek-like voice, and with solid, traditional art, I can't imagine anyone not being charmed by these stories.
Recommended for: readers of all ages, I think. Maybe someone who's read a few superhero comics before, and isn't so interested in the action, as that is not the focus in these comics, on the whole.
2. Ex Machina
Brian Vaughan must get really tired of this comparison but I think this is a pretty apt description... it's The West Wing meets superhero comics!
Ex Machina is the story of a man who is the world's only superhero, who can speak to machines after a freak accident, who becomes the mayor of New York. The comic follows him as he's just been elected, as he tries to stay out of the superheroics.
In the exact same way that you couldn't imagine finding a TV show about the workings of a political office interesting but in the end found it fascinating, BKV turns the everyday political intrigue of the NY mayoral office every bit as exciting as the superheroic bits. The art is incredible and manages a trick that I've never seen before: it's lifelike, while remaining full of life and atmosphere. I can't recommend this series highly enough, and in any other list would have been number one.
Recommended for: everyone.
1. Top Ten
Oh Alan Moore. You have written some excellent comics, and if I think about Watchmen, Swamp Thing and League of Extraordinary Gentlemen, and I'd allowed it, this top five might have mostly featured you. But this comic series, which is comprised of two 6-issue trades, one spin-off mini (Smax) and one original graphic novel (Top Ten: The Forty-Niners), is my favourite of the lot.
It's the story of a rookie cop starting out on her first day as a member of the Top Ten, a police precinct, in a world of superheroes. Which doesn't sound that brilliant but it just is!
It's maybe not as earth-shatteringly beautiful or profound as some of Alan Moore's work, but it has to be the most entertaining, and the one with arguably the most heart.
I could read and re-read these books forever, they are so dense with smart artistic nuggets, character moments, and gripping cases. I want to read them all again right now, in fact!
Recomended for: all human beings with souls.