This new, Jim Lee-designed outfit (yeah, really) is part of Wonder Woman's #600 issue extravaganza, where J. Michael Straczynski will start writing along with a brand new origin. Check it, courtesy of JMS himself:
I actually have no problem with the gods rewriting WW's origin -- seems a fine way to straighten the character out -- but I don't know that Diana growing up on the mean streets straightens anything. I'll leave it for you guys to ponder in the comments, although I'm especially interested in hearing what the nerd girls have to say. (Via DC's Source)
The Gods, for reasons of their own but which may have something to with their survival and perhaps the survival of Earth itself, have changed the timeline. In the new timeline, years ago the Gods removed their protection from Paradise Island, and left it vulnerable to attack. And attacked it was. Led by a dark figure, a veritable army descended upon the Island, equipped with weapons that could kill even the Amazons. Outgunned, doomed, Hippolyta gave over her three-year-old daughter to a handful of guardians who spirited her away as Hippolyta led one last desperate battle against the forces that had come to destroy all she had created. In that final battle, she and most of the Amazons were killed, though some managed to escape.
It's now nearly twenty years later. Diana has been raised in an urban setting, but with a foot in both worlds. She has little or no memory of the other timeline. She knows only what she's been told by those who raised her On the run, hunted, she must try to survive, help the other refugee Amazons escape the army that is still after them, discover who destroyed Paradise Island and why...and if the timeline can be corrected or not. She also does not yet have access to her full powers, but will be gaining them as she goes. Along the way, she will face a range of enemies -- human and otherwise -- who we have not seen before.