Seems like sixto has been focusing on the DC side of comics, which is all well and good. But there are other companies and imprints out there, such as Marvel, and Vertigo. Vertigo, by the way, is usually described as "DC Comics, but for adults." Many of the well known, highly acclaimed comics, such as Transmetropolitan (future Hunter S. Thompson fighting against corruption and evil and being a huge douchebag the whole time), Preacher (a preacher's quest for god. So he can kill Him.) and Sandman (The epic story of the King of Dreams, Morpheus. Deals with a lot of mythology, the nature of stories and the like.) as well as a host of other just-as-good-but-not-as-well-known comics such as Hellblazer.
Again, Sixto seems to be focusing on the DC Comics side, so i'll cover some of the great Marvel comics, regular marvel continuity as well as the Ultimate Universe.
For the regular marvel universe, hereafter called 616 marvel, there's Captain America Volume 5 by Ed Brubaker, which is the current one. It covers Cap's discovery that his old WW2 sidekick, Bucky is alive and being used as a brainwashed assassin for old soviet remnants, and goes on from there. It's a spy thriller in comic form, definitely one you wouldn't want to miss.
If you're more interested into good pulpy fun, there's Matt Fraction's Immortal Iron Fist, which is like a kung-fu action movie in comic form. Has fighting tournaments, has old 1930 style pulp stories, and it even has KUNG-FU TREACHERY!
Over in the Ultimate Universe, there's Brian Bendis' Ultimate Spiderman, which is a retelling of Spiderman stories for a more current generation. Its got great dialogue, great villains, and less teenage angst than you can shake a stick at.
Before I go, I'll leave you newbies, and those who are old hat at the whole comic thing, one last piece of advice, that should be followed.
Avoid Jeph Loeb comics other than his Colors series (Hulk: grey, Daredevil: Yellow, Spiderman: blue, etc) and his old Batman stuff (The Long Halloween, etc).
AVOID HIM, LEST YOU READ A COMIC WHERE THE RED HULK BEATS UP A CHARACTER OF COSMIC POWER THAT STANDS BESIDE GALACTUS THE DEVOURER OF WORLDS IN POWER LEVELS!