Mainichi, that's the latest trend-- basically a move from the frilly princess to the rocker, a look that has certainly been around for quite some time but which appears to be gaining ground.
Currently the tsuyome joshi has several sub-sets, the "trend tsuzui kei" (trend follower) who leans to the '80s punk avant-garde, the "mezase kirei kei" (aspiring beauty) who aim for a more mature look by wearing boyish clothes, and the "ganso tsuyome kei" ("original" type, mostly visual kei fans who wear heavy makeup and go all out in their costuming), and who are reportedly not thrilled to be the next big trend. And then there are the fence-sitters: "switch kei," who only occasionally don the tough-girl look.
Basically, it sounds like a move away from "kawaii" (cute) and more into "kakkoii" (cool). Though I can't help but notice that the outfit worn by the "mezase kirei kei" girl looks like something I'd expect Miley Cyrus to wear.