Our favorite runway trends aren’t usually about the clothes - instead they’re subtle shifts that signify something social, something cultural, and something that almost everyone can do at home.

This season, it seems to be hair color, which has been dulled and deepened until yellow blondes and platinum blondes have all but vanished from the runways.

Some of this season’s biggest newbies are Masha Tyelna, Ali Stephens, and Heloise Guerin - all with ashy brown hair. Meanwhile, Mariacarla Boscono seems to be making a major runway comeback, with hair restored back to its natural brown (two years ago, she reigned supreme on the runways with a brand new white-blonde bob).

Meanwhile, Jessica Stam, Tanya Dziahileva, and Karlie Kloss seem to have toned down their sunkissed streaks to match Abby Lee’s chamomile tint, and the white-blonde girls among them - Agyness Deyn and Sasha Pivovarova - have crawled home sick.

Does this mean we can cancel our appointment at Bumble & Bumble, and grow everything out?

The LA Times has a story this week about blondes with roots, and it’s so insane it actually makes sense:

Writer Monica Corcoran asserts that brown roots with blonde hair is “the latest way to feign indifference to your appearance” - if $300 shredded jeans, threadbare designer t-shirts, and anything by Martin Margiela doesn’t really work for you.

Her proof is a slew of rooted celebrities, including both Olsens, Madonna, and even Jessica Simpson, plus Los Angeles stylists paid hundreds of dollars to paint “lowlights” and darker roots onto their fair-headed clients.

There’s also a new wig from the Raquel Welch collection that comes with built-in roots, and a stash of Marilyn and Brigitte Bardot photos showing the sexbombs with their own dark scalps.

Corcoran surmises the tarnished blonde hair represents a good-girl-gone-bad complex, and her argument is both persuasive and intriguing.

Still, in our ash-blonde experience, we can also say those dark streaks growing in are less good-girl-gone-bad and more good-girl-gone-broke.

It must be those $300 jeans that were carefully run over by a monster truck before hitting Barneys…

More proof that blondes will rule the Spring ‘08 campaigns, despite the hype of industry diversity:

Tanya D. will join Anja Rubik in the DSquared campaigns. When we try to imagine Helen of Troy, we usually picture Tanya, though presumably she’ll be styled less classic for the antics of Dan and Dean Caten in their latest ads. The Siberian model is now seventeen.

Meanwhile, WWD reports that blonde and banged Kate Moss was snagged by Donna Karan for her new Spring ‘08 spreads, a job that belonged to brunette Catherine McNeil last season.

We’re thrilled to hear about Tanya’s first booking for Spring (she’s so pretty! she’s so magical!) and we’re always down for another few pages of Kate. But it’s interesting to note that yet again, a very vocal piece of the industry has done nothing to sway the actual practices of it… at least not yet.

Also: When we go to Bumble + Bumble next week for our semi-annual color fest, we’re actually thinking of going dark brown… is this so totally wrong?

Despite the diversity discussion off the runway this season, it seems Spring 08’s golden girl is literally the fairest of them all, at least if we’re going by ad pages.

Anja Rubik, 22, has racked up the most campaigns so far, including Valentino, Oscar de la Renta, Belstaff, DSqared, H&M, The Gap, and Neiman Marcus’ art of fashion special. She’s very cool and very gorgeous, and resembles something of a fairy princess built from stone. Like Mariacarla Boscono two years before, her new campaign rocket seems to come partly from a gutsy decision to chop off all her hair.

We suspect a close second in the campaign race will be another Fashionista favorite, Jessica Stam, who’s also blonde, pale, and stop-your-tracks gorgeous.

Meanwhile, blondie Vlada R. racked up some of the most runway miles during Fashion Week [Supermodels.nl rated her at the top of the pack, but BryanBoy did a very thorough investigation and totaled Kasia Strauss as the winner]. Regardless, both have skin that’s practically see-through, and eyes to match - just like Lily Donaldson and Snejana, both of whom also stomped many miles this season.

We really love Anja, and Stam, and we’re thrilled to see their new ads.

But the diversity discussion of the past three months seems like the skinny discussion of last year - talk that seems to send action in the opposite direction.

But there is one blonde style star who’s going for a change - Sarah Jessica Parker, whose reddish brown hair is new, yet constantly photographed around New York.