Updated 08/08/11:
This picture of Yuja Wang was published in the LA Times from a recent Hollywood Bowl concert. She's wearing the same dress I've been yammering on about. Photo by Lawrence Ho of the LA Times.
Since almost every reviewer of Tuesday night's chamber music concert featuring Yuja Wang and members of the San Francisco Symphony has mentioned "the dress" (granted, not with the same enthusiasm of yours truly) I thought it a public service to direct you to the best picture I've been able to find of it

I also shared it on the Facebook page for this blog. Go ahead, "like" it- you know you want to.