The new issue of Entertainment Weekly has a bit on Joss Whedon writing and directing Wonder Woman and mentions what the costume will NOT look like:
A “Marvel boy,” Joss Whedon never really connected with rival house DC Comics’ Wonder Woman, but now the guy’s madly in love with her and is gonna write and direct Warner Bros.’ long delayed feature! “She represents something absolutely pure,” says the Buffy creator, who says his Amazon will not, repeat not, wear “star-spangled panties” a la Lynda Carter’s TV incarnation. Whedon now sees it as a match made in fanboy heaven. “When I was mulling this over, my friend said, ‘Joss, look at your freakin’ resume. You have two things on it: wonder and woman. That’s all you write!'”
Thanks to ‘pimpernel’ for the heads up.