Okay, if you want a great story about mid-career Batman, go out and buy Hush volumes 1 and 2 immediately. Do not hesitate. If you need further convincing (and I don't doubt you will) then read on.
I first learned of the Hush story from friends on the web. Originally a 12 month story arch from the monthly Batman comic, one of DC's tentpole publications, this comic stands almost perfectly on it's own two feet as a graphic novel, which I can attest to since I don't buy monthly comics outside of the occasional trade paperback.
First off, Jim Lee's art is amazing. He strikes that elusive blend of style and realism that I seek when looking for a good artist. He doesn't go over-the-top and come off looking impressionist like many artists who have handled Batman, and yet he doesn't slip into the borigness of straight-up reality. His anatomy is solid, his environments are believable, and his women are beautiful. I'm an aspiring artist, and Jim Lee is definately an inspiration. If nothing else, buy it because it's a book full of great Jim Lee Batman art.
As for the story, I've got to hand it to Jeph Loeb. When I read volume 1 the story seemed to be mostly an excuse for Jim Lee to play around in the Batman world and draw lots of it's favorite characters. But when I read Volume 2, it was a completely new ballgame. Most recent Bat-stories have fallen into the trap of meeting and maintaining a status quo. Hush is one of those rare stories that doesn't just change the status quo, it destroys it. I won't spoil anything, but I'll tell you that it has some pretty big impact on the Batman mythos, and unlike many recent comics it manages to evolve the story in ways that some will condemn, but others like myself will praise.
Basically, without spoiling too much, the story is about Batman at the top of his game, but someone is organizing his enemies and Batman ends up wrapped up in a waist-deep conspiracy against himself. The plot is chock full of huge twists and surprises that I'll admittedly didn't see coming. In between the juicy details are some good action scenes with alot of great action with famous Bat-villains, some great dialog and character developement for Bats himself. And if you like Catwoman, HUSH offers one of the best stories about Batman's relationship with her I've read, and I found it very touching. The whole thing is a genuine rollercoaster of intruguing plot twists and solid character developement, and I was surprised at how well it kept me guessing.
Overally, HUSH is definately a quality Batman story. If you've already had your fill of "early years" Batman stories, buy yourself Hush volume 1 and 2. Jim Lee's gorgeouse art with Jeph Loeb's compelling narrative is a genuine home-run for DC, and I really hope they come back together in a few years to give us another one.